I think you need to work on tiles, tags, and SEO to be found. I looked at this listing:
http://www.etsy.com/listing/119394039/art-print-life-is-like-a-box-ofI would make sure to add printable to your titles and tags, (and there was one typo in office in this listing at least.) Go back through everything and change them up a little bit. You have some cute stuff; I think if you can target your niche market you will do fine.
Also, try either printing them out and showing the prints frames, or set each image onto a landscape background for the first image, so that the whole image can be seen first thing, and the show them closer up in the second and third frames. This will help attract attention. Keep adding listings, so you can be found in the sea.