Maybe you have a few favorites. Another kind of short poem is the haiku. But here are a couple of haiku-influenced poems by Cid Corman, who lived many years in Japan and knows its poetry well. If these look casual, look again, and see if you can notice their formal structure or formal principles. I'll limit myself to three.
Mountain stars eyes in the open do Rain-drops.
Each makes a point of silence. What's heaped too high spills Emptiness just fills. A blind child Guided by his mother Admires the cherry blossoms.