I've looked many places for him in history books about Asia, and he is barely mentioned in anything. For someone who conquered almost all of Asia you'd think they have more about him.
Because any affect that Genghis Khan had on the world was indirect. He didn't build cities. He didn't start a dynasty. He didn't halt the progress of a country. Sure there's a city, a dynasty, and a halt of progress that can be tied to Genghis as a cause but indirectly not directly.
P.S. The city is Karakorum. The dynasty is the Yuan dynasty. The country is Iraq.
It's relative. Genghis Khan is talked about lots in Mongolia. Alexander in Europe, Qin Shi Huang and Cao Cao in China, Nobunaga and Toyotomi, Hideyoshi in Japan, etc. The list goes on. Many many important characters in history are glossed over and misrepresented because people don't want to admit that some person in some far off place did something greater than their hero.
I'm assuming you don't live in Asia, hence why you don't hear more about him.