Mathematics: First, go through all the knowledge points roughly and classify them into 1. Don't look at what you have mastered, just pass every exam; 2. Mastering part can be improved; I have hardly mastered it, but it is not completely out of my control. Focus on improving these two parts, do more exercises and consult teachers and classmates, and strive to master 80%. You find it difficult, but you can't master it. Give up, and then do as much as possible during the exam. Usually don't need to spend too much energy. Try it when you meet it. If you think it can be solved, then fall into the third category to improve, or give up if you are not sure. Remember, you can consolidate, improve, and give up.

Literature review: read more, read more and understand more. Memorizing everything will be tiring and unrealistic, but if you read a lot and have a sense of language, many answers are actually first impression questions.

Finally, if you have the courage to admit your shortcomings and seek solutions, you will certainly make progress. I wish you find a suitable learning method as soon as possible.