It's probably lost over time, so it would be difficult to find something that gives appropriate advice and does not get lost in stories itself. There are at least 3 concepts that differ very much in detail. One is from the beginning of the last century and probably was written to get famous, not from felt knowledge. If you want to know what your body knows on it, touch the lower part of the pot belly we qigongers have (
) holding it with a flat hand and the other over it on the arm, holding it like a child, and then just breath, feel, wait. That helps more than anything written by other people. This is about the connection of human to the eternal, by feeling, advice, helpful memories and emotions, and energetically. Better not mix it up with stuff other people wrote in not too sure state of their mind. There could be very interesting stuff, but how to tell it from the wrong. If you really want to learn what the classical medicine tells about it, you need to find a really good TCM expert who can tell you, and who has results. If he regularily treats ill people successfully and knows what he does, he could perhaps elaborate if he feels like it. Otherwise you do like I told and hope that your eternal part likes the idea and starts writing messages, to your intuition, and heart.
Ming Men Revealed? 
