People with thin, flat chests and small breasts can help their breasts develop by adjusting their diet and exercising more if they are still in the developmental stage. If you have already passed the developmental period, you need to improve through breast augmentation surgery. 1. In the developmental period: in the developmental period of women, you can eat more rich in vitamins and protein-rich food, but also to do more exercise, the purpose is to help the development of breasts, to improve the situation of flat chest and small breasts. 2. Past the developmental stage: If a woman has passed the developmental stage, it is difficult to help breast development through food and exercise. You need to go to the hospital to find a professional doctor, and eventually, you will be able to improve the situation of flat chest and small breasts through breast augmentation with autologous fat or breast implants and other surgeries. Consult a professional doctor for specific remedies.