Auto-translated
2 Frosty So let's figure this out from the very beginning...
Did you visit all three obelisks???
If so, a puzzle map has opened for you (R key). In the center of it, a cross marks the spot where the Tear of Ashi is buried. This puzzle displays a part of the actual map; find that area and position your hero approximately on the cross. Then dig (a full move is required), the digging key is D. If a message appears like "there is something slightly to the northeast or south there," move your hero one cell in the indicated direction and dig again. When it says your search has been successful, the artifact will be in your inventory; run back to the Castle and build it.
P.S. The thing about the magnifying glass was just a figure of speech.... Meaning you take a real one and study the screen with it 8)) Sorry for misleading you...
Let me know if it's still unclear, then I'll play the mission again and send screenshots of all the steps with explanations.