UPDATE:
Hello again! I would like to update this discussion.
Today at night my wife told me that she heard a knocking at our door of our sleeping room. As she described it I came to conclusion that she heard the same knocking that I heard before. It is a very similar knocking which I heard with my internal and physical ears (knocking coming from another plane, more likely from astral, and which can be heard when you are asleep, but are returning to your physical body (similar when you make astral unfold, similar state when you start to see dreaming images, but are not fully asleep) with your astral body and as well this sound seems to reach even physical ears).
She did not open the door because she thought it would be unsafe (as I did not open before). We are 100% sure that it was not a physical person in our house, but some kind of not physical entity/person.
We sealed our room carefully with strong "magic" before this event, so my speculation would be that knocking astral (or ethereal?, not sure about ethereal) person/entity was asking for our "permission" to enter our room, because it could not enter because of seals.
We have sealed this room by putting sulfur in four corners, drawing pentagram on the threshold of the door with charcoal, also by putting some salt there and there and also at the door, and pouring some ashes (which I scrupulously prepared couple of years ago and left sealed in red/white painted glass jar for energetic charge for couple of years).
As I understand it is the same thing/person which was bothering us by knocking at our furniture some time ago (before the seal).
Also our missed things were not found yet.
It is really bothering us as it seems it is not regular acts of "sorcery".
We will wait for any insights as long as you need. We know that to give some advice about this matter takes much time to investigate.
Thank you again for your time.