Keyword Searching Principles 
 

When you search by keyword you search using terms that you are familiar with and that seem appropriate for your topic. This type of searching is useful when you do not know the appropriate subject heading or when no suitable subject heading exists for your topic. Keyword searching allows for combining terms in a variety of ways based on the following principles:

Boolean Operators

The operators AND, OR, NOT combine terms using Boolean logic.

 

                                                                           

AND   Connects terms to retrieve every record in which all of the
            specified words appear, regardless of their position in the records. 
            AND is usually used to combine unlike concepts.  AND narrows the search
            since each term specified must be present.
   

        
                                                                           

                             humor AND healing                         
                                                                                             
                                                          cancer AND caffeine

                      

OR      Connects terms to retrieve every record in which either, both, or any one
            of the words appear, regardless of their position in the records. 
            OR is usually used to combine like concepts, synonymous terms,
or variant 
            spellings.  OR broadens the search.
                                                                      

                lawyers OR attorneys                      
                                                                                                                  
                                                               england OR britain

                         

            NOT Excludes any words following NOT and retrieves records in which only
            the first term appears. The NOT operator should be used with caution to avoid
            eliminating relevant records. NOT narrows the search because it excludes terms.
                                                       

                                                                                                                                                                                   surfing NOT internet                            

 vikings NOT football

NOTE: In some databases you only need to type NOT,  in others, such as theTruman Library Catalog, you need to enter AND NOT. 

Remember that keyword searching with Boolean operators suggests that a relationship exists between the words in your search statement. Therefore omit words such as value, benefit, results, relationship, and effects from your search statement.