You can begin your search from the main library search box, located at: LBBL.NSU.EDU
Type in your keywords and click the "Search" button. You will get a list of results. In the menu on the left side of your screen, you will see a variety of filters. If you scroll down, under "Content Type" click the box "Peer Reviewed" this will limit your results to only peer reviewed material. You may need to refine your search further or change your keywords to find what you need.
The NSU library offers a variety of databases that allow you to filter for peer reviewed articles. All the databases are available here: A-Z Databases. Many offer this same type of check box or filter for peer reviewed materials.
This guide will help you with filtering your search results for only peer-reviewed or scholarly articles: Library 101: Searching and Filtering