Apps filter only module which application = true so you can add that 'application' : Ture in __manifest__.py file.

If your app considered as fully-fledged application you can set application to true,otherwise leave it  False and its better to follow the standards.

Here you are the manifest application field description:

application (bool, default: False)Whether the module should be considered as a fully-fledged application (True) or is just a technical module (False) that provides some extra functionality to an existing application module.

More Details Here