I can't speak for China, but in India there has not been a historically large amount of attention paid to writing textbooks in mathematics and physics. During h

I can't speak for China, but in India there has not been a historically large amount of attention paid to writing textbooks in mathematics and physics. During high school, the students who seek challenging problems often fall back to Russian text books, especially in physics. More recently there has been a push by some Indian authors, so you will find some challenging texts by Indian authors, but still nowhere close to say Krotov or Irodov for physics.