Knock, knock. 。Three knocks on the door broke the silence. Yesterday afternoon, Hualing brought Mengbao to the address Cheng Keqin had given them. She was a little nervous as she knocked. 。The one who opened the door was an older person, seemingly the housekeeper of the family. 。"Hello, I'm Cheng Keixin. I was introduced byscussing and sharing Traditional Chinese Medicine. Would you be interested in taking a look"Xu Zui Ning heard his words and became thoroughly interested."What kind of app are you talking about"Liang Z...