I've followed the instructions on https://docs.microsoft.com/en-us/powerapps/maker/portals/configure/search-additional-entities to add 4 custom entities (Track, Album, Artist and Playlist) to global search on a custom portal / portal from blank.
This seems to work as far as I can see the entities in the search field filter and I see the correct number of results in the search facets (I see the number of Tracks, Albums, Artists and Playlists). However, no search results are displayed and I receive this heading: No results were found for this query. I believe the web template is Faceted Search - Results Template.
Has anyone else experienced this? If so could you share the settings you've used? There seems to be confusion / inconsistency with which should be set with logical names vs plural names and I wonder whether that's what's causing the issue. I could be totally wrong and maybe there's an additional step to extend or recreate the search results template...
Also, I've found that lookup fields tend to be ignored by the search despite adding them as columns in the Portal Search view and the query site setting for each entity.
Thanks very much for any help!!