Use the letters to open the box closer to you near the other box: L, O, S, S. Take the dagger handle.
Look at the painting to the right of the bookshelf. Use the hammer to break it.
Use the eye vision to see the dagger blade inside, then take it.
Place the dagger pieces into the dagger mold on the table and use the finished dagger on the door keyhole to open it.
Proceed to the next Can You Escape the Dark Mansion 2 level!
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