If you are looking through the keyhole at something that you shouldnt be looking, it means that you will hurt someone. If you see another person who is looking through the keyhole, it means that you should be careful with those people who are around you, because they might betray you. If you are looking for the keyhole, but are unable to find it, then it means you will fail at your friendships by stupid mistakes.
Keyhole dream meaning
Read more about dreaming of Keyhole in other dream meanings interpretations.