where query from relation table in laravel

1UserModel::whereHas('attachments', function ($attachmentQuery) {
2    $attachmentQuery->where('level', 'profile_level');
3})->get();
4If you want from already queried model get specific attachments then write
5
6$userModel->attachments()->where('level', 'profile_level')->get();
7
8it is impossible to query both UserModel and AttachementModel in single query,
9it must be at least two queries. Even fancy 
10  UserModel::with('attachments')->get();, 
11which returns user with all attachments, do internally two queries.
12
13OR:
14
15I noticed that you can define relation constraints within with method
16
17UserModel::with(['attachments' => function ($attachmentQuery) {
18    $attachmentQuery->where('level', 'profile_level');
19}])->get();