Why did people who studied Liu Ren in ancient times have a low level?

One, Qimen, Taiyi and Liu Ren are three types of ancient legends, and * * * has the same skill category as Yin-Yang and Five Elements in divining good or ill luck. Second, the difference: the six masters focus on personnel (humanity), Taiyi focuses on national natural disasters (heaven), and Qimen focuses on local (tunnel). 1, strange door: the meaning of "Taoist magic" consists of three concepts: strange, door and Dunga. "odd" refers to b, c and d; The "door" is the eight doors of rest, birth, injury, supervision, scenery, death, shock and opening; "Escape" means hiding. "A" refers to Jia's six, namely Jia Zi, Jia Xu,,, and Jia Yin. 2. Taiyi: also known as Taiyi number, it is a skill number, the first of the three, and it is an advanced prediction in ancient times. It is said that Taiyi style was produced when the Yellow Emperor hit Chiyou. 3. Six people: Also known as Six People Shinto, it is an ancient divination category of Yin-Yang and Five Elements, which is called three types together with Daoism and Taiyi Shenshu. According to legend, it has been more than 5,000 years since Xuan Nv gave Xuanyuan Huangdi nine days to destroy Chiyou.