I have a trick that has enabled me to progress thru many levels.

Combine a blaster with a diamond, noting that the blaster must be swiped to the diamond. (If you swipe the other way ie. diamond to blaster then all the blaster will explode at once after the coloured squares change to blasters).

Ok so you've swiped blaster to diamond. All the coloured squares change to blasters of that colour. They will then start blasting quickly in order top row column, left to right.

However, here's the trick:
After the first couple blast, if you have two blasters that changed next to each other - swipe them! All the new squares that fell onto the screen in the same colour will change to blasters too, extending the amount of blasters that will explode. You can time this to break more glass squares or put out fire or dig. The kicker is that each swipe of the changed colour blaster-blaster combo doesn't count as a move. Hence you can possibly do this 5 or 6 times, getting extra turns for nothing.