There's two aspects of learning for all subjects; remembering and understanding.
If you're having a problem with just remembering facts like the parts of the human ear, then I'm sorry but you've got got to memorise it. Keep looking at it, ask friends to test you, read again and again and it will eventually sink in. This aspect of studying is worst for Air Law and Operational Procedures.
However, if you're having problem understanding some concepts like visual illusions with different runways (for example), then your brush up course should help (mine did!). However, once you've understood the concept, then it's easy to remember and apply to any question of that type thrown at you.
If there are specific areas of difficulty, don't forget your ground school is there to help you; email them, call them and go through a problem.
Cheers
Whirls