All the goal tiles on level 87 are hidden under the crates, and to beat this level you need to remove all the obstacles as quickly as possible. There isn’t much room, and you don’t have much time, so don’t hesitate!
Matched a few pieces, and now new ones take their time falling down? Don’t wait for them to stop – switch to a different part of the field and make matches there. Don’t see any matches near the crate you were trying to destroy? Turn your attention to a different crate. This way you won’t waste any time and will easily get through the level.
You should also check out this video that shows how we got through level 87.