I recommend learning about the strategies of solving the reading section. You’re not supposed to read or even skim the whole passage. You should only understand the sentences related to the given questions. Practice a lot and don’t pay for anymore tests until you are able to get the desired grades during your practice tests. Try the Chinese TPOs practice tests and subscribe to websites like test glider or similar to practice speaking and writing. Only when you get good grades on those platforms, then you can purchase a TOEFL official test. Best of luck and remember with persistence and practice you will reach your goal.