Research is a little like trying to put together the pieces of a puzzle.
When perusing databases, journals, books, and various other sources, take note of the names of people who are often quoted; scholars who are doing research on your topic and the universities with which they are affiliated; spokespersons, and influential figures; and then search for articles that are written by them.
Check the bibliographies and footnotes in the articles you come across, as well as suggestions for further reading.
Do these sources seem relevant or pertain to your topic? If so, does the library have these materials?
Can you locate them through other databases or through interlibrary loan (interlibrary loan is a service by which you can receive books and photocopies of documents that are owned by another library).
Patty Clark, Sue Erickson (Library Director), Sherry Matis, Sophie Rondeau, Stephen Leist