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Advanced Search Tips: Home

Learn tips on how to search more effectively in the Library's catalog and databases.

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These are more advanced tips for searching in the Library catalog or a database. If you need help developing keywords before you get started searching, check out our guide on Brainstorming Keywords for a Search.

What are Boolean Operators?

The large number of citations in the library's catalog and databases may require one to limit otherwise broad or general searches in order to get a manageable (and relevant!) number of results. That's where Boolean Operators come in. They allow one to limit or expand their search depending on the need. 

AND - tells the database to include results that have both of the terms you're searching which will narrow your results

                                                                   two circles overlapping. the circle on the right white with the word travel, the circle on the left is white with the word Europe. In the space where the circles overlap it is filled with the color yellow.


OR - tells the database to include results that have any of the terms and is used to expand your results


                                                                   Two circles overlap and are filled in with the color yellow. The circle on the left has the word college in it and the circle on the right has the word university.

NOT - tells the database to exclude results with a certain word thereby narrowing the search


                                                                   two circles overlapping. the circle on the left is filled with the color yellow and has the word television. the circle on the right is white with the world cable.

Using Boolean Operators in the catalog

When searching in the box on our homepage, you can use Boolean operators right away:

screenshot of the All search tab on the library's home page. in the search bar are the terms GMO and environmental safety. The search button on the right hand side of the box is circled in red.

However it might be easier to go to the Advanced search to better format your search:

Screenshot of the All search box on the library's homepage. Below the search box is the link Advanced Search which is circled in red.

In advanced search, you'll see AND is the automatic option. Put one keyword onto each line:screenshot of the advanced search box with the terms solar power and global warming.

If you click on the AND, a dropdown with the other Boolean Operators will appear:

screenshot of advanced search with the terms solar power and global warming. AND OR NOT appear in a dropdown for the user to select

Remember that AND will help narrow a search, OR will expand it. Notice the different search results here:

Screen shot of the advance search with the terms solar power and global warming. The number of results 98,091 is circled in red.

Screen shot of the advance search with the terms solar power and global warming. The number of results 2,694,851 is circled in red.

Remember NOT can be used to help limit a search. See in this example below how more than one Boolean Operator can work in a search:

screenshot of the advanced search with the terms solar power and global warming not windpower

Boolean Operators in Library Databases

Boolean Operators are in our databases too and work the same way. You can add as many lines with keywords in a search as you'd like:

screenshot from database Academic Search Premiere with the keywords television and streaming services not cable in the search bars

Wildcards and Truncation

Wildcards and Truncation are other search strategies you can use to help narrow or expand a search. All of our databases should support these operators.

Truncation - uses a symbol at the end of a word to find different variations. The symbols most commonly used are *, !, ?

Wildcards - uses a symbol to retrieve variations of letters within a word. The symbols most commonly used are ?, $, *

? Search: wom?n Retrieve: woman, women
* Search: educat* Retrieve: education, educate, educated, educator, educators

Search eight$ Retrieve: eight, eighth, eighty

! Search: gr?y Retrieve: gray, grey

Some databases vary on which symbols they prefer you to use. You can find this out in the Help documents of a database or if you need further help, ask a librarian!

More Search Help

In need of more search help? Check out these guides:

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