Thanks.
I'm planning to make new sketches, paintings, etc. every day to improve my chance of being admitted. The guy who judged my work said I was talented but he also told me to make much, much more artworks in all disciplines (paintings, drawings, sketches, 3D artworks, photographs, etc.). I only took some photographs, a couple of sketches and some paintings. I'm planning to do a couple of realistic paintings with different kinds of paint (I usually use Acryl, but I also have oil), many, many sketches and drawings with different materials (chalk, charcoal, etc), make some 3D stuff (maybe carve a stone or something). He also told me to focus on more realistic stuff, so they could see how I interpret objects, landscapes, etc. I usually make abstract artwork (which was really nice, he said, one of the reasons he let me pass) but I have to show all aspects of my creativity.
I have about 3 months to do this, so I'll just spend a couple of hours a day on art.