When you jump across the water to the side of the woods where the ghost is the stones will be to your right if you keep walking straight. You'll see a first set first and it isn't that one, keep walking until you see a second one. There will be a bunch of them on the floor but only 3 of are Dew Stones!
This is the map from that area, maybe it will make it clearer:
http://fmarsault.perso.monaco.mc/MMMAPS/PN/PN04.JPGHope this helps!
