A great way to find more articles for your project is to use the Reference sections of articles. You can do this two ways: 1) look in the Reference sections of articles you already have, or 2) use a handy feature in PsycINFO that looks ahead to see which later articles cite the article you have.
To check this out, we'll look at a Psychological Bulletin article by Rosenthal and Ambady. Start a new search and enter those authors' names (one name per field) into the search fields for "AU Author".
One of the references that pops up should be: Thin slices of expressive behavior as predictors of interpersonal consequences: A meta-analysis.
If you click on the Cited References (188) link, it will show you all the references for that article. This would be just like flipping to the References section of that article.
If you click on Times Cited in this Database, it will show you all the later articles that cite this article. That number can help you recognize articles that have had a large impact, because many later authors cite this article. In addition, some of the Cited References or the articles in the "Times Cited" can be useful sources for you.