How can a fortune teller know my last name quickly?

He set in advance which pages are radicals, which can be combined with which pages, and which can be combined with which pages, until finally it can be determined as a word or a pronunciation; Because I can't tell fortune, it's completely analyzed, so I can't give you a detailed explanation. It also said something about looking up the dictionary. Isn't looking up the dictionary a step-by-step confirmation? Selecting words by radical: first find out where the radical is, then find out where the radical and the radical match, and then find out which page the word you need is on. At this time you already know where the words are, but when you don't know the specific words, there are many words on this page. When you open this page, you can see where the specific words are. He can also know which word you are talking about on this page through technical settings, and then know what word it is.