If you're looking only for articles--including scholarly, peer-reviewed journal articles--use the dropdown menu beside the main search box to select "Articles."
Enter a few important subject-related keywords in the search box and hit the "Search" button.
You can narrow your results even further on your search results screen. If you're only interested in articles from Scholarly, Peer-Reviewed journals, look for the "Limit To" panel and click the box that says "Scholarly Sources." Your results list will be updated to weed out non-scholarly sources.
This video produced by the American Psychological Association shows how choosing keywords in a specialized thesaurus can improve your search results.
This tutorial--created by North Carolina State University Libraries and shared via a Creative Commons license--provides a detailed overview of what is meant by "the Literature," different varieties of literature reviews, and the steps involved in completing one. Though the title of the video refers to graduate students, the content is also valuable to undergraduates working on literature reviews.