Harevydent is on the right track with his edit. I think you should experiment with something other than a very top-down perspective that you are currently using.
While the dragon, ruins, and person hiding are supposed to be the main subject of the piece, the big opening to the ocean on the right side of the canvas is very distracting -the subjects of the piece are too out of focus. I don't mean to sound rude saying this, but I think a fair analogy of your piece is that it looks similar to a cave painting in the sense that while it is telling a story of sorts, the composition is lacking and makes it not as interesting as it could be.
I would really suggest you also watching these 3 part, 5 min videos that give a very brief insight into how composition and telling a story with a piece works.
https://www.youtube.com/watch?v=1McYZX6KScg Reading about composition and studying other works will take you a long way, would recommend you take the time to search around for some articles/tutorials!