One of the best frog top surface lures for snake head / toman is the Lure Factory Mega Frox. This lure is designed to mimic a frog swimming on top and leads to great chances of being struck at. Comes in a variety of colours and patterns for different conditions.
The lure has a 2 lead ball bearings in it, that create a rattling increasing the chances for a strike.
The lure is 100% hand painted, so each piece is unique.