Hi and welcome, Catherine!
The biggest thing, and I hate to say it, but you really do need more listings. Think of each of your listings as another "ping" out into internet world and a chance to get more people in. Can you offer something similar? Different sizes? Try to think about ways to tweak.
Also, I wouldn't start your listing name with 'custom order.' The first three words are the most important, so starting them with Canvas Periodic Table for Baby or something similar might be more effective.
Since you're selling something very specific, I'd recommend advertising heaviliy off of Etsy. Since this is such a huge market, you're going to need to find a subset for your speciality.
Finally, I would definitely recommend you check this out:
http://amandajocrafts.wordpress.com/2012/09/21/on-helpful-tips-for-etsy-sellers/especially for the section on tags.
Best of luck!