Research Skills for Developing Writers: Language for Effective Searches
AND, OR, NOT: Refining your Search
You already have learned many techniques for refining your search. You can narrow by the publication date, source type, author, or title. Sometimes regardless of the subject terms or keywords, you may find that you need to broaden or narrow your topic because you get too few or too many results. This means that combine two or more search terms to get more relevant results. Using "AND", "OR", or "NOT" can help you achieve better search results.
Using "AND", "OR", or "NOT" will help you find more or find fewer sources about your topic in a database. Here is a summary of how each one works:
- AND: will find sources that have both search terms in any part of the text
Example: Searching solar AND energy will find periodicals that contain both of these terms.
- OR: will find sources that have one or both search terms in any part of the text
Example: Searching sports OR statistics will find periodicals that contain one or both of these terms.
- NOT: will find sources that have the first search term, but not the second search term, anywhere in the text
Example: Searching human rights NOT United States will find periodicals that contain only the term human rights, but not the term United States.
Video: Boolean Operators "AND", "OR", "NOT"
Together, "AND", "OR", and "NOT" are called Boolean operators. Watch this video about using "AND", "OR", and "NOT" in searching from the University of Auckland Library in New Zealand.