how to search everything

Question

We have a Wordpress intranet using BuddyPress, bbPress etc..

From this article, I adjusted my theme's searchform.php to include:

<input type="hidden" name="post_type[]" value="docs" />
<input type="hidden" name="post_type[]" value="events" />
<input type="hidden" name="post_type[]" value="forums" />
<input type="hidden" name="post_type[]" value="posts" /> 
<input type="hidden" name="post_type[]" value="pages" /> 
<input type="hidden" name="post_type[]" value="topics" />

However, when we search for content written inside a Wordpress page, the search does not find this content.

This fact makes me wonder if the search is working properly or not.

The search results page reaches a URL like:

www.example.com/?post_type%5B%5D=docs&post_type%5B%5D=events&post_type%5B%5D=forums&post_type%5B%5D=posts&post_type%5B%5D=pages&post_type%5B%5D=topics&post_type%5B%5D=doc&s=document

I have tried including singular and plural but the issue remains:

<input type="hidden" name="post_type[]" value="docs" />
<input type="hidden" name="post_type[]" value="events" />
<input type="hidden" name="post_type[]" value="forums" />
<input type="hidden" name="post_type[]" value="posts" /> 
<input type="hidden" name="post_type[]" value="pages" /> 
<input type="hidden" name="post_type[]" value="topics" />
<input type="hidden" name="post_type[]" value="doc" />
<input type="hidden" name="post_type[]" value="event" />
<input type="hidden" name="post_type[]" value="forum" />
<input type="hidden" name="post_type[]" value="post" /> 
<input type="hidden" name="post_type[]" value="page" /> 
<input type="hidden" name="post_type[]" value="topic" />

Confused.

Help appreciated.

Update:

If I add

add_action( 'admin_footer', function() { print_r( get_post_types( [ 'exclude_from_search' => true ] ) ); } );

to functions.php, I receive the output:

Array
(
    [revision] => revision
    [nav_menu_item] => nav_menu_item
    [custom_css] => custom_css
    [customize_changeset] => customize_changeset
    [wp_router_page] => wp_router_page
    [forum] => forum
    [topic] => topic
    [reply] => reply
    [buddydrive-file] => buddydrive-file
    [buddydrive-folder] => buddydrive-folder
    [bp-email] => bp-email
    [bp_docs_folder] => bp_docs_folder
    [vc_grid_item] => vc_grid_item
    [bwg_gallery] => bwg_gallery
    [bwg_album] => bwg_album
    [bwg_tag] => bwg_tag
    [bwg_share] => bwg_share
    [tribe_venue] => tribe_venue
    [tribe_organizer] => tribe_organizer
    [deleted_event] => deleted_event
    [rtmedia_album] => rtmedia_album
    [thrive] => thrive
)

Answer 1

The main search uses any custom post types (when you don't set post_type query var) so if you're missing public custom post types from that, then most likely those custom post types are registered with exclude_from_search as true.

Check if the plugins have filters to change that or try e.g. to override it with:

add_filter( 'register_post_type_args', function( $args, $post_type )
{
    if( in_array( $post_type, [ 'foo', 'bar' ], true ) && (bool) $args['public'] )
        $args['exclude_from_search'] = false;

    return $args;
}, 999, 2 );

where foo and bar are some custom post type slug examples that are public.

In bbpress forum and topic post types are registered public but with exclude_from_search as true (src). Also note it's singular and not forums and topics.

We can check for public and search excluded post types with:

$types = get_post_types( [ 'exclude_from_search' => true, 'public' => true ] );

that might contain an array like this one:

Array
(
    [foo] => foo
    [bar] => bar
)