Cao An, who had been a Taoist priest for more than ten years, only learned the art of praying and martial arts. Dzogchen asked the gods to go down the mountain to drive away evil spirits and was almost beaten to death; the martial arts that reached the state of perfection could not break a brick...so that he always thought that there was something wrong with what he was practicing.
It wasn't until his soul traveled through the world of Gaowu that he discovered that the problem was not the content of the practice, but the world.