The vinegar paste is really necessary. I remember reading a book before. This is true, not a scam, and I don't know much about vinegar paste. Being jealous is good for my health. I used to go to school in the countryside, but it was cold in winter, and the teacher would make a stove for us to keep warm. If I catch a lot of colds, the teacher will cook some vinegar on it, saying it can kill bacteria, which is quite useful.