Filter inside document not showing all results (from reference in search)

Ok, so the references showing in a document, besides being shown in a way that doesn’t work for me (cfr. Backlink references are showing sorted by date or separated by rem, how to go back? ), are not filtering adequately. As you can see, there are several rems that contain both “substancia” and “Spinoza”:

However, when I filter it with that tag (the result is the same if I do it as text search), it only throws back one instance:

So, any idea what is happening? Is this a bug?

Thanks!

I also experience the same thing, I think it is a bug. Wonder if developer could answer it as I also use filter extensively.