Professors often require students to include articles from scholarly or peer-reviewed journals as resources for their research papers. These articles are authored by experts in their fields and are reviewed by their peers before being accepted for publication. The level of scholarship is high above what we might find in a news magazine.
Clicking the boxes to guarantee that your results are full-text and peer reviewed (scholarly) articles will result in finding the types of college level publications that your professors are looking for.
Using the dropdown arrows to the right of the search boxes will insure that your search terms appear in areas that make them stronger, like in a subject heading or abstract, rather than just a random spot in an article.
Performing an "Advanced Search", which allows you to enter a number of terms and use boolean logic to link them, will result in a smaller number of more precise articles that are spot on with the search terms you entered.