Three or nine days is a time division of winter in ancient times. From winter to Sunday, every nine days is a cycle. Therefore, March 9th, that is, the 27th day of the winter solstice, is the proverb of practicing March 9th in winter and three days in summer, which is the hottest and coldest time of the year. Traditional Chinese medicine often says that winter diseases are treated in summer, and summer diseases are treated in winter, which is complementary to yin and yang. Sanjiu Moxibustion, as its name implies, is moxibustion on the human body for three or nine days, which is moxibustion. You only need to choose in a specific period, so it is called Sanjiu moxibustion. Yang Qi: That is to say, there is a positive breath of hair growth. In order to be healthy, people must be full of Yang Qi and full of vitality, so as to prevent various diseases. Therefore, it is necessary to supplement Yang Qi, and the people's sense of justice is sufficient. Hope to adopt, the knowledge of traditional Chinese medicine is very complicated, and several paragraphs are not clear. This is just a general story. Thank you.