What does the mountain doctor mean by the mountain of divination?

This "mountain" refers to Feng Shui, which means "seeing Feng Shui".

The five techniques of Huang Qi in China's ancient medicine-mountain, medicine, life, physiognomy and divination-contain the secrets of self-cultivation and physical exercise. In ancient times, most monks chose to practice in the quiet mountains, which is the origin of the word (mountain).

The remaining four items in the five methods of ancient medicine in China are:

Medicine-contains the secret of treating diseases, and its method is different from modern medicine. (Mountain) and (medicine) are for four kinds of life (life, old age, illness and death).

Inevitable pain, a secretary seeking relief.

Fate-including the skills of understanding human beings, transforming human destiny, making human beings know their own destiny and doing their best.

Bu- contains the secret of predicting the situation and handling it accurately.

Phase-contains the secret of observing the reasons of things and making choices.