I don't know much about fragrances, so I was wondering this, too.
You could try doing what Gary Vaynerchuk did/does. His dad had a wine store. When Gary was younger his had owned a wine store. Gary wanted to know how to recognize the flavors in wine, so he practiced eating and smelling those flavors.
So if someone in a wine magazine said a wine had the taste of dirt in it, then Gary would try dirt. If someone said it tasted like cherries, then he would try cherries.
Here is a video where he shows what he did/does:
Also, maybe you can buy very small samples of individual scents and practice smelling them.