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Searching and Browsing

How do I search for a resource?

You can search for a resource in two ways. To use the Keyword Search, type your search term into the Keyword Search box and either hit return or click the button next to the box. To use the Advanced Search, visit the Advanced Search page, enter your search term(s), and click the Search button.

What is the difference between Keyword Search and Advanced Search?

Keyword Search allows you to search for one word or phrase without any customization of the search process. It will locate your search term(s) anywhere in the resource record.

Advanced Search provides options to refine your search strategy, including searching for combinations of words or phrases, limiting the search by a variety of variables, and customizing how you will see the search results.

What are the best search methods?

A number of strategies allow you to maximize your use of Quick Keyword Search and Advanced Search:

  • Capitalization is irrelevant. For example, NASA is equivalent to nasa.
  • To search for an exact phrase or number, enclose the search term within double quotes (e.g. "Library of Congress" or "114,457").
  • The search function assumes a string of words is joined by AND. It will match records with all the words occurring in the searched fields either together or individually. (For example, a search for University of Wisconsin will return all records that include University, Wisconsin, and University of Wisconsin.)
  • To exclude a specific word or phrase from search results, add a dash before it (e.g. -magnesium or -"potato chips"). To require that results contain a term or phrase, add a plus sign before it (e.g. +magnesium or +"potato chips").
  • The results will automatically be displayed in a descending order of relevance, with the most relevant items at the top. You may also sort results by the Title, Alternate Title, or other field as determined by the site administrator. Relevance is determined through a combination of word occurrence frequency and a weighted value of the metadata fields being searched. Word occurrence in the Title field is weighted the heaviest. The Alternate Title, Creator, Publisher, Classification, and Contributor fields are in the next lower tier of weight values. Occurrence in the Url and Description fields are given the lowest weight values.
  • Advanced Search allows you to refine a search or search within certain metadata fields using dropdown lists. The portal software by default offers the following metadata fields as Limit options: Url, Date Issued, Resource Type, Language, Audience, and Format. These limits can be used exclusively or in combination with search terms. You may select more than one option from each Limit by highlighting the desired options from the list. To select a value(s), click on Show Limits to reveal available options. Highlight the desired value(s).
  • Faceted Search is a way to filter the results of a Keyword Search or an Advanced Search. Find out more about Faceted Search below, in the section titled What is Faceted Search?.
  • If your search does not yield the kind of results you are looking for, click the Refine Search button to be taken back to the advanced search page with your previously-used search criteria already loaded.
What is Faceted Search?

Faceted Search is a way to filter the results of a Keyword Search or an Advanced Search you have performed.

After conducting a Keyword or Advanced Search, you will receive a comprehensive list of results that meet your stated search criteria. You may, however, wish to narrow your search results even further to find those resources that best meet your needs. Faceted Search is great way to do so.

On the Search Results page, you will see a column titled "Narrow Your Search”; this is the menu for Faceted Search. Beneath this heading are the names of various fields (e.g. resource type, format, language, etc.), also called facets, which can be used to filter your results.

Filtering with Facets

Click on the "+" sign displayed beside each facet name to expand the options for that facet. A new list of search terms will appear below the selected facet. Click the search term you want to use to narrow the search, and the search results will be filtered based on this criteria.

You may make use of any number of facets to filter your search; applying multiple facets results in a Boolean AND search. For example, a search for the following would retrieve instructional videos on manufacturing:

Searched for:

  • Format contains Video
  • Resource Type contains Instructional Material
  • Keyword contains manufacturing

Applying multiple search terms under a single facet also results in a Boolean AND search. For example, a search for the following would retrieve civil war materials that are available in both English and Spanish:

Searched for:

  • Language is English and is Spanish
  • Keyword contains civil war

To minimize a facet, click on the "-" sign displayed next to the expanded facet name. Minimizing a facet only hides the list of search terms from view; it does not remove any filters from your search.

Refining your Results

A list of your applied search criteria will appear on the page with your search results. This list includes both the criteria set in the original Advanced Search, as well as any chosen filters applied using Faceted Search. For example:

Searched for:

  • Format contains Document -- PPT
  • Resource Type contains Professional Development
  • Keyword contains nanotechnology

To remove any of the filters applied using the Faceted Search menu, simply click the "X" next to the the bolded search term in the Faceted Search menu. You can also narrow your search results by using the "Refine search" button. Unlike the facets, "Refine search" allows you to edit your keywords and search terms.

What are search operators?

Search operators are symbols that are added to search queries in order to more finely control the results returned by the search. A number of search operators can be used in the Keyword Search box to define search terms with a greater degree of specificity:

Phrase Searching

You can search for several words next to each other by enclosing them in quotation marks:

  • "a key phrase"

Excluding Terms

If you want only results that do not mention a specific term, you can exclude that term by prepending a minus sign:

  • -unwanted
  • good words -bad -words
  • words we want -"phrase to exclude"

Exact Matches

To match a word or phrase exactly, immediately precede it with an equals sign:

  • =National Nanotechnology Network
  • =

This is usually used with URL and Controlled Name fields. Exact match differs from phrase searching in that with an exact match, the content of the field has to be identical to the search string to be considered a match.

Date Ranges

You can search for dates within a specific range by entering a beginning and end date separated by spaces and a dash:

  • June 10 2008 - July 19 2010
  • 5/1/04 - 2/10/12

Ranges are inclusive, and most common date formats will work.


To search for values before or after a certain date, precede the date with the appropriate operator:

  • > 2009 (after 2009)
  • <= Feb 20 2010 (on or before 2/20/10)

It is also possible to specify relative to the current time:

  • < 90 minutes ago (less than 90 minutes ago)
  • >= 10 days ago (10 or more days ago)

Comparisons also work with numeric fields:

  • >= 42 (greater than or equal to 42)
  • != 65535 (not equal to 65535)

For dates, most common formats will work. Comparisons are only for Date, Timestamp, and Number fields.

How do I browse for a resource?

To browse all resources included in the database, visit the Browse Resources page. The number in parentheses to the right of each topical subject gives you information about how many sub-topics or records are associated with that topic heading. Topics get more specific as you drill down. To go back to previous topic level(s), click on them at the top of the page or use the back button on your browser.

Where can I find a list of the newest resources?

The New Resources area can be found on the home page. This list contains the most recently added resources.

See Also

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