What does "Jade Sagger" mean?

People in China always want to get lucky when they do things. Whether in politics, business, study, travel, marriage, hunting and fishing, or even a haircut, we must find an auspicious day. The book Jade Sagger is said to have been written by Xu Zhenren, a Taoist priest in the Eastern Jin Dynasty. As soon as this book was published, it was very popular in the local area and became a necessary bedside book for every family. Jade sagger was supplemented by later generations, and many different versions were derived. Its contents cover everything, from sacrifice, marriage, work, travel, opening business, farming, saccades, tinnitus, dreaming, weighing bones, even matching cats and dogs, and all kinds of strange divination.