Middle-aged and elderly people have more social experience and time. After reading the above (in fact, you can't help but watch it repeatedly when you enter the door), it is more correct to read the classic original books "Book of Changes" and "Huangdi Neijing", or you can buy them online;
Dangdang, JD.COM Mall ... Just click on the title you want to buy on Baidu, and many choices will pop up. You can send the book to your box in half a day, or you can choose to pay after receiving the book, which is very convenient.