What kind of gobbledygook did Master Guiguzi leave him?

Before Guiguzi's master died, he gave Guiguzi a roll of bamboo slips with the word "gobbledygook" written on it: What kind of gobbledygook did Guiguzi's master leave him? . Guiguzi opened it and found that there was not a word in the book from beginning to end. Guiguzi is puzzled. He thought hard for a while, but he didn't come up with a result. At that time, he felt nothing, nothing, and empty, so he got into his cave and fell asleep. It happened that I couldn't sleep. Guiguzi tossed and turned, always thinking about those bamboo slips without words. Until dark, bamboo slips were still rolling and rolling. He just climbed up, lit a torch in Song Mingli and read this "gobbledygook" again by the light. This scared him to jump up, the bamboo slips were shining with golden light, and the lines of tadpoles were shining. Guiguzi sighed, "Is this Jin Dian handed down from ancient times?" Guiguzi's interest doubled at one time, and he read it in one breath and recited it from beginning to end. It turns out that there is a vertical and horizontal letter on it, which talks about coitus, reaction, infighting, confrontation, flying pliers and other techniques.