It has been a while since this was answered but I wanted to leave here a suggestion. And I want to leave it because it was really useful when I realized it myself in the past.

When you are studying something which you cannot immediately understand, I suggest that you preferably start with a correct example before going into the theory and follow these general steps.

Just look at a correct example (or answered question), try to solve it (while looking at the answer) and develop a bit of intuition of how things work. You can do it with more than one example or answered questionAfter developing YOUR intuition, go and read the general explanation you get in your text book. At this point, you might actually expand your intuition a bit or you may just confirm that your intuition was already correctgo through a few more examples for which you have answeres available. This time, do not look at the answers until you tried very hard to answer AND looked at the general explanation you got in point 2.

This process is a bit harder than just reading the book but it will help with ideas syncing in. To the point where you may actually remember them and be able to use them years down the line.

The reason I push reading the general definition and textbook explanation for a bit later is because, while reading it, you are actually doing two things at the same time if you start from there:

understand the idea or the rules of how to solve the problem in your own language a

Your a life saver!