Show how relevant your thesis statement is to the topic. Keep your topic precise. Let the reader know what you will explore and what are the limits that you will not explore during the course of your essay. Your thesis statement should guide the outline of your essay. You should search for your topic by subject heading to get the most relevant list of resources.
Books tend to contain a more general overview of the topic.
Check the index or table of contents for your topic within the subject. Certain chapters may prove to be very useful. Books are located by using library catalogues such as Novanet. Journal articles tend to provide more recent information on a narrower range of the topic. Use indexes and databases to locate journal articles on your topic.