If searching doesn’t find the right emails in Mail on Mac
If you don’t get expected results when you search for email messages in the Mail app on your Mac, try these suggestions.
If one or more mailboxes are selected in the Mail sidebar or the Favorites bar, Mail searches only those mailboxes. To search all mailboxes, click All Mailboxes in the sidebar.
Mail may not be looking in the Trash or Junk mailboxes, or searching encrypted messages. To include them when searching all mailboxes, choose Mail > Settings, click General, then select the options.
You may need to sync the mailboxes on your Mac with those on the Mail server. Choose Mailbox > Synchronize > [account].
Mail may be excluded from Spotlight searching. To check, choose Apple menu > System Settings, then click Siri & Spotlight in the sidebar (you may need to scroll down). Go to Search Results on the right, then select the Mail & Messages checkbox, if not already selected.
The Mail folder (located in your home Library folder) may be excluded from Spotlight searching. To check, choose Apple menu > System Settings, then click Siri & Spotlight in the sidebar (you may need to scroll down). Click Spotlight Privacy on the right, then if Mail is listed, select it and click the Remove button .