The quickest way to knock down an enemy is to vault over him, by pressing Towards + A, then striking with your sword. However, more powerful monsters block this move. All monsters throughout the game are either red or blue in color. All the red monsters can be vaulted over. The blue ones block and strike back. During a battle, quickly dispatch all the red monsters first by vaulting, striking, and retrieving. Then finish off the blue ones by either blocking until they strike, then counter-attacking (they will be off-guard), or by freezing them with a dagger stab, then slicing with your sword. This method will get you through battles quickly and more efficiently, while still allowing the retrieval of a decent amount of sand.