Is it permissible for me to use the book "Tafsir Al-'Ashr Al-Awakhir" (Interpretation of the Last Ten Surahs) and the clay comb that I found under the bed, after asking the brothers in the room and none of them knowing their owners?

We advise you to leave the book and the comb in their place, as their owner may have forgotten them. However, if you have already left the place and taken them with you, then you may benefit from them. This is because the book might be something its owner donated, and the comb is among the items of low value that one who finds them is permitted to use. You may also place the book in a cultural center or educational institution and give the comb to someone in need.