Dear Gopal Shete,
Thank you for posting your query in our community.
Please don't worry, let's resolve your concern together and move towards a path towards resolution.
- Can any other user search the file? We would like to know if you are the only user who has the problem.
- Is the specific file not searchable? If not, please try searching from a different document library and let us know the affected scope.
- Did you ever try searching with "prefix +*"? For example, the file name is "testfile.xlsx", please search with keyword "test*"
- What is your permission on the site? Please try assign a different permission to yourself in this way:
Go to SharePoint site >> site permission >> advanced site permission >> check permission.

- Please try re-index the site and the library, wait for 24 hours and check the result.
Please refer to this article for more information about re-index --->> Manually request crawling and reindexing of a site, a library or a list - SharePoint in Microsoft 365 | Microsoft Learn
If you have any additional questions or if you need any additional help regarding this or anything else at all - let me know, I'll be here to help you out.
And in the meantime, I hope you'll have a lovely day ahead, stay safe & take care!
Yours sincerely