So basically when the grass in this place runs out, they drive the cattle and sheep to another place to eat grass in another place, and so on, they don't even know where they are. So they often bury people in a place after death, then kill an old sheep in that place, and then use the lamb to find the grave, but once the lamb dies, it can never be found again.
This is how the tomb of Genghis Khan was handled. After being buried at that time, those horses were used to flatten the tomb from above, which means that you look basically the same as the grassland from above. Then you can still find it by this lamb in the first two generations, and you won't find it in the future.
Culturally, they don't like the Han people to build their own tombs before they die. They will feel that as the sons of the grassland, they belong to the grassland after death and do not need additional funerary objects. As Xu Zhimo said in that poem, I came gently, walked gently and waved my sleeves without taking away a cloud.
This concept of tombs led some emperors in the Yuan Dynasty to be buried in a crude way. You don't know where they downloaded it, and history books won't record it for you, because the status of Han people was very low at that time, and you didn't have a chance to know these things. Then, after the erosion of time, no one knows more about the war.