How do fortune tellers know what happened in your past?

A person's birthday is your personal information. After many calculations, your information will be displayed. According to the Book of Changes, plus the principles of 24 solar terms, heavenly stems and earthly branches, Yin and Yang, Ke Sheng and so on, 5 18400 programs can be produced. Coupled with geographical location, hundreds of millions of programs can be generated through names, allowing you to accurately judge all aspects of a person's information. Why are some inaccurate, that is, they have not learned anything, or have a little knowledge? There is a 25-year-old man on QQ who has studied the Book of Changes for 30 years. Who do you think will believe me? I have been afraid to talk about getting started for decades. Some people say that I understand everything after reading the Book of Changes. This is a misunderstanding, I don't understand. I don't know much about the Book of Changes. This is learning and introduction, so you should distinguish between true and false when calculating.