same filter.
I don't want to commit to it either, and I'll search for them for years if I have to, don't get me wrong. But sometimes trails go cold, and you do all you can, and you still don't find anything. Sometimes it's better to close the book for a little while instead of obsessing over it and going crazy. Until there's a reason to open the case again, that is.
I guess what I'm saying is, sometimes it's better to let people have the idea of disappearing into thin air and going back home, even if we still don't stop looking. It's an explanation, even if it's based on a lack of evidence to support any other theories.