Hi @Shanmugam, Suresh,
Thank you for posting in this community.
Unfortunately, SharePoint Online does not support searching for the names of attachments in lists. This is by SharePoint design.
As we know, the main function of a list is to display or record relevant data and not to save files. Therefore, attachments in SharePoint lists can only be found when viewing the details of each item.
You can use this feedback platform to raise your issue, which will help the SharePoint team to take note of the problem and consider its implementation. Your contribution is highly appreciated. :)
Please accept my sincerely apologize for any in convenience this may cause. Thank you for your kind understanding.
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