First of all 350 views and a sale in 4 days (especially your first 4 days) is pretty stellar. I didn't get my first sale from a stranger for 2 months and after 10 months I average about 200 views in 4 days.
I only looked quickly, but for starters you need a lot more items to be found on Etsy. I know that takes time, but do the best you can to get as many items listed as you can.
Also it looks like you need to learn about SEO (search engine optimization). You will find teams about SEO here on Etsy. Learining about SEO will help you with tags and titles which is how your items get found on Etsy. Your tags should be more than one word and I don't think your titles will help you get found in search. I don't know a lot about titles and tags for art prints, but I would think it would be more beneficial if some of your titles started with the type of print it is or a simplified version of the subject matter. Think about what shoppers will type in search. Will they type in realistic kid with a demonic twist print or will they type in just demonic print, or type in terms that describes your type of art?
Instead of melting mushroom print I would maybe use just mushroom print first because the first 2-3 words in your title are the most important and the word melting will reduce your relevancy for mushroom print which is more likely to be what someone will type in search. Then you can add other keywords after the main one of mushroom print. Same with the holding skull print. I would use just skull print first for the same reasons.
Find a team and learn all about SEO. Then what I said will make more sense. The SEO teams will also teach you how to be found by search engines like google. Good luck, you've already got a great start!
