Before starting your library research, reflect on your subject or research question and decide on some keywords, then combine your keywords with useful boolean operators.
If a research question focused on the impacts of armed conflict and war on the diets of people in medieval periods, for example, the keywords might be:
After determining the best keywords, select useful boolean operators to define the relationships between the keywords so that your search tool provides the best results possible.
Here is a list of the most common operators
| Operator | Usage | Example |
| AND | Combines two or more keywords - narrows the search | food AND war |
| ( OR ) | Retrieves synonyms or related words - expands the search | (food OR diet OR nutrition) |
| NOT | Eliminates the word the follows - narrows the search | medieval NOT renaissance |
| " " | Searches multiple words as a string - makes searching more precise | "armed conflict" |
| * | Truncates the root of a word - expands the search | war* (will find war, wars, warring, warmonger, etc.) |
You can combine all of these techniques into one search string, such as:
("Armed conflict" OR war*) AND (food OR diet* OR nutrition) AND medieval
If you would like more assistance with keyword searching and search strategies, consult this text, or email the librarian.