What does it mean to look up the eight-character library?

Eight-character library is a superstitious method used to predict personal fate and fortune. The information in the eight-character library is usually based on the theories and terms in traditional fortune-telling and divination books, but this information is for reference only and should not be used as the only basis for decision-making.

Gatekeeper, a Chinese word, means guarding the gate; Metaphor is to check and test something or behavior according to the prescribed standards.