Watch for the tiles to flash if you're having troubles finding a match. Try to make matches lower in the game field to increase the chance of getting chain reactions. The Spade and Hammer bonuses are effective at destroying tiles in tricky parts of the game field. Try to save all your bonuses for more complicated levels. When you are very close to finishing a level go for as many chain reactions as possible to get extra points that will bring you bonus lives. Some rows in the game field are shorter than others. Try and move the artifact pieces to the shorter rows to release them faster. This strategy works for releasing the bonus items as well.