Why do some fortune tellers calculate accurately?

Now, there are many liars. Get to know something about you through talking with you, and then guess your things, such as the surname on the roadside. I don't know if you've tried. I just gave you a lot of paper with many surnames on it. Give him your last name, and he will know your last name. Do you think it's amazing? In fact, there is a scientific basis. There are detailed explanations on the internet, and only he can count.

Another possibility may be true, but such people generally don't do the math for others. Even if there is, it should be disabled, because as far as I know, such people have missed too many outdoor machines (not kidding), which has caused this situation. Besides, these people will not ask you for money when they tell fortune. They will give you as much as you like, and he won't say anything. The above is just my own understanding. I hope it works for you. If it is good, please give points.