Personal opinion experience:

First of all, believe the platform, I personally believe in Tmall or Jingdong Mall, the official mall to buy sales better, often the quality of both qualified, the price is also more affordable, remember to buy the official flagship store.

Secondly, if you are not afraid of being expensive, then choose to buy the Tongrentang brand, no matter online or offline physical stores, there is no Chinese medicine brand in China that is more trustworthy than Tongrentang.

Third, find a friend who knows about herbal medicine and ask him to recommend or buy it for you.

Fourth, improve your knowledge about the subject, Baidu Encyclopedia.