Why should we search for a patent before applying for a patent?

It can make the applicant know the technical status of the technical field and judge whether the patent application is patentable. If you find that the same invention has been applied for before, you don't need to apply again; If it is different from the existing technology and still obtains a patent after retrieval, the protection scope of the existing patent claim can be avoided, thus ensuring the quality of the written application documents.