I just got some of my exams back, and I didn't do well because the questions seemed very different from the problems I practiced. I spend about 3 hours per day for each subject, but for classes like physics it takes me about an hour or more to solve a single problem so I can only solve about a dozen or so problems a week. Anyway, none of the techniques used in the exam were involved in any of the most difficult textbook problems I attempted, so I don't know what I did wrong for the problems I can't figure out. If I ask some physics faculty here, they tell me to go to my own professor, and when I go to my professor he tells me to figure it out on my own. Nobody else in the class knows how to solve them either. I'm amazed at how people before PhysicsForum/the internet checked their answers. But since the exam problems are harder than the problems rated the most difficult in my textbook, should I use a different textbook to study?