A few days ago in Weibo, I saw someone mention the "four elephants catching dragons" in futures trading. Does anyone know what it means? Which book talked about this tactic?

China Railway published the book "Practical Trading Techniques for Futures Traders", which pointed out that "Four Elephants Fighting Dragons" is a practical futures trading technique originally created by author Li. The four elephants refer to the black dragon, suzaku, white tiger and Xuanwu, which are derived from the Book of Changes and Taiji Bagua. "Four Elephants Catch Dragons" is a futures trading philosophy founded by Li, which combines China traditional culture with basic knowledge of futures, including Suzaku tactics, White Tiger tactics, Qinglong tactics and Xuanwu tactics. High-quality futures varieties can be found through the tactics of catching dragons with four elephants.