Why are there many duplicates (in medicine) in the invention patents searched by China National Intellectual Property Administration?

Have you applied for this patent before? If it is, it is a loophole that often appears in the review. Your patent can be said to be valid or invalid. Yes, this patent also exists. However, anyone has the right to claim that your patent is invalid. Similarly, if not, then you don't have to worry. After his patent is passed, you can apply for invalidation of his patent.