What does the half moon on the nail reflect?

Reflect the human body's heat and cold. The little finger doesn't have a moon, but the other eight should. If the finger moon does not exist, it means that the patient is seriously ill and the patient's body is very cold; If there are thumbs and middle fingers, this situation indicates that there is moderate coldness in the body; If there is no little finger, the rest of the moon is very small, and the patient's constitution is cold.