What is the central topic of Feng Shui after Guo Pu's Buried Classics in Jin Dynasty?

Since Guo Pu's Funeral Classics in the Jin Dynasty, the theory of "Qi" has become the central topic of Feng Shui, and all specific ancient geographical activities must be carried out mainly through getting Qi. It requires that man's small universe qi must be in harmony with the surrounding environment's big universe qi, and make great achievements by using the qi of heaven and earth, which is the most basic viewpoint of China's geographical view. Therefore, ancient geography was particularly taboo about "dead breath", "holding one's breath", "discouraged" and "leaking air", believing that it would bring bad luck, let go of financial resources and even lead to diseases.