What do the "dragons, caves, sand circles and water hugs" in Feng Shui refer to?

Long Zhen: It is the most important cause and effect in Feng Shui. It must be Xinglong dragon, not weak dragon, sick dragon or stegosaurus. The dragon needle point is real, otherwise there is no point or a fake point. Sand refers to sand protection, that is, the two sides of the cave are surrounded by Qinglong and Baihu sand. Water hug: refers to the water in front of the acupoint that surrounds the acupoint in a semi-closed way, and the water between the famous hall and the mountain.