Before you begin searching for sources, identity keywords based on your topic, research question, or argument.
Try a test search using your keywords. If you get too many or too few results, try changing your keywords. You may need to broaden or narrow your topic.
For a comparison/contrast essay, don't use the words compare or contrast in your search. If your essay is comparing the health benefits of karate and tai chi, search for each element individually:
Need help finding the right keywords? Ask a librarian!