Below you'll find the databases most often used in Communication research, but the resources you need will vary depending on your topic. Ask me if you're not sure where to begin your search. I'm glad to help you!
Use subject headings to create narrowly tailored search queries.
Subject headings constitute a controlled vocabulary that can help you find sources by their primary subjects. The Library of Congress maintains this vocabulary, making it standard across many different databases and catalogs.
For example, imagine you're developing a topic on theme parks. Searching that term in LC's subject heading thesaurus reveals the preferred subject heading, "amusement parks." Using the advanced search interface in a given database, you can change the search field from keyword to subject as pictured below. Searching "amusement parks" in the subject field returns all results tagged with that heading. Now cross-reference your subject search with keywords specific to your interest in amusement parks, such as the way they're marketed.
Caveat searcher! Narrow queries of this kind may inadvertently filter relevant results. It's often best to begin with broad, keyword-based searches before moving to subject headings.