Your secondary research may point you to particular cases that are significant to the subject you are exploring.
Case law is made up of the decisions made by judges in court cases and tribunals. In the common law of Canada, judges must follow previous rulings (judgments) of higher courts when the ruling addresses the same issue. Judges can also use the rulings of other cases at the same level of court to help with their own decisions.
Tracking down relevant cases is therefore a very helpful and important step in your legal research process.
There are two main options for finding case law. Canlii is a free resource with comprehensive coverage from 2001 onward. Quicklaw is a more in-depth database with comprehensive coverage from 1986.