If more than one word is entered, the search system will find documents that contain both of these words (i.e., they will be ANDed together). In the following example, both searches will retrieve the same documents:

nicotine cancer
nicotine and cancer

You can also use the Boolean operators AND, OR, or NOT in combining search words. Search terms can be "nested" by placing them inside parentheses. You can also the wildcard symbol when you want to search for part of a word. The wildcard symbol, an asterisk (*), can be used anywhere with the search term.

nicotine and cancer

retrieves documents that contain both nicotine and cancer

smoking and (addiction or abuse)

retrieves documents that contain either the words smoking and addiction, or smoking and abuse.

nicotine not cigarettes

retrieves documents that contain the nicotine, but not cigarettes.

passive smok*

retrieves all documents that contain words starting with smok (e.g., smoke, smoking, smokes, smoked) and that also contain the word passive.