People are unpredictable, and things are unpredictable. I don't understand human feelings. What do you mean, you can't pierce the bait hides the hook?

It means it's hard to guess what people are thinking. Things are unpredictable, people's minds change as they say, and the world is cold. According to the network language, this sentence means that people's inner thoughts, feelings and intentions are difficult to be speculated or predicted by the outside world, and it is a word to advise not to trust others easily.