What is the meaning of Liuhe in pitching?

The ancients were superstitious, and marriage should choose a good day, and the six words of year, month and day should be appropriate, such as Jiazi Year, Ugly Moon and Bingyin Day, which are called Liuhe.

Another way of saying this is that the moon is combined with the sun and the morning light, that is, the ugly child, the yin and the sea, the hair and the air, the Chen and the unitary, the old and the Shen, and the noon, which is called Liuhe. Peacock flies southeast: "It is convenient to reopen the book according to the calendar, and Liuhe just corresponds this month."

Another meaning of "Liuhe" refers to the corresponding changes of the four seasons in twelve months of a year. Huai Nan Zi. Time is training ":"Liuhe, Meng Chun, Qiu Meng, Zhongchun, Zhongqiuhe, Ji Chun, QiuJi He, Xia Meng, MengDonghe, Midsummer, Zhongdonghe, Late Summer and Jidonghe. "

"Liuhe" also refers to heaven, earth, east, west, north and south. Zhuangzi's Theory of Everything: "Beyond Liuhe, saints exist regardless."

As for the sentence you mentioned, I don't know the source. There is often a saying of "pitching heaven and earth" and "looking at six rivers". According to the last explanation, it refers to the whole world. For example, Jia Yi's On Qin: "Ruling Liuhe with Supreme Power" and "Taking Liuhe as Home", and Li Bai's "Ancient Style": "The king of Qin swept Liuhe and wanted to see it."