Destroying the ice tiles first will give you more space for removing Acorns from the stream. Then, get rid of the Boxes in the lower part of the field. Use the stream to collect Gnomes from the sides of the field and get power-ups to hard-to-reach places. Matches in the lower part of the field will help clear the top of the field too, which will make collecting Gnomes easier. Explode power-ups to charge the Rainbow Blast and use it to collect Acorns.