Tomb \\ Tomb of the Witcher George (The Witcher 3: Wild Hunt)

The meaning of the topic is this, I went around the square to look for the armor of the griffin school in the Tomb of George, I found things in the final large hall, but there is a passage further and there I saw this wall and a sign on it (a hint that needs to be done) but I did not understand what , tried to open with all the signs, blew up and beat with a sword and sense 0, tell me mb who knows?)

about