In this you can see that dried vegetation has also been applied to the walls as well as the roof. These layers protect the harder layers inside from water and other elements of nature. The inner layers are usually made from natural material like mud and clay, although at times brick is used.
Related images: Sketches of traditional Indian houses or Photos of thatched huts from the Chennai area (on which the sketches on this post are based) or Photographs of houses and huts from Dakshinachitra in South India (these are the old traditional houses of South India) or Huts in an Indian Village (huts with cobbled roofs)
For ancient Chinese architecture: Chinese style architecture sketches of the Forbidden City