Limit to or exclude specific post types

Hi, I’m trying to use Jetpack Search in combination with Sensei LMS. We need the search to only show results from the Lesson post type.

Is there a way to either only include certain post types (I’m not talking about the manual filter in the widget, but automatically limit search to certain post types for all searches) or, if not possible, exclude certain post types or posts/pages?

Thanks ??