You can find peer-reviewed articles in a variety of places.
UC Search – The library catalog is a record of all items that UC has access to, including scholarly articles. Filter your search on the left hand side menu to “Peer-Reviewed Journals”
Subject Databases – These databases are organized by topic and primarily collect scholarly articles. Find the ones recommended for your subject in UC's Research Guides.
Google Scholar – If you are not finding enough results through the UC Search and Subject Databases, you can cast a wider net through Google Scholar. Bear in mind that if UC does not have access to the article you find, you might have to request it through Interlibrary Loan.