@rockgeek
Shame there isn’t any direct support for it here
There isn’t because this is not related to ACF directly. It’s related more to the WordPress database structure (on which ACF relies) than to ACF itself.
Implementing such a functionality doesn’t depend on how the post and fields have been created. So it makes no difference if you defined field using ACF, other plugin or even manually using WordPress native custom fields support.
Firs of all you should read about WP_Query and how to write meta queries. If you want to filter existing query (add/remove/modify) then pre_get_posts filer will be useful.
If you want I can send you a simple example of a search form built this way.
