when Content Approval = Yes -> Documents no longer show up in Search

As a Site Admin, when I set Content Approval = YES for a Document Library in Versioning Settings, documents in this library no longer show up in search results, both at library as well as site level, and regardless of Approval Status (draft, pending or even in approved).

Same happens if the Content Approval setting is left unchanged, but I set Draft Item Security = Only users who can edit items.

Also, if I try reverting the changes to the original configuration of when the library was created, still the documents do not show in the Search results. I end up having to delete the library and recreating it.

Lastly, this setting seems to disable the email notification when the @mention is used in a comment in a document in this this Library.

Please allow the documents in a library that has Content Approval setting active or Draft Item Security set to users who can edit, to be searchable, and @mentions to be notified by email. 

Thanks!