You cannot set Advanced Search for Super Users only. But you can avoid the indexing of Email addresses in Settings/Users

It would be the responsibility of the users to control who can see what.

Best regards, Pascal

I guess there are other entities/categories the users can search in the advanced search, right? If you switch off indexing doesn't mean that the checkbox in the pull-down vanishes 😉

Let me check after my holidays. As user privacy is respected on your site anyway, the non-shared mail-addresses won't be retrieved by these searches anyway, right?