Before that. When Zhou was in the elevator, he met a Chinese man.
Zhou held down the elevator that was about to close in time, allowing the man to come in. The man glanced at Zhou and expressed his kind thanks. His skin was slightly dull, and Zhou guessed that he might be a Vietnamese man. It wasn't until the man got off the elevator that he turned around and said thank you to Zhou.
Here, it is actually easy to identify Chinese people.
Conception: