Fred notices that while google.com searches with site:ibiblio.org retrieves over 7.6 million results. The same search on google.cn only returns 1.6 million.

Things do vary. I just got 4,220,000 for site:ibiblio.org on google.com and 1.6 million on google.cn (as Fred did).
But when I add tibet to the search as in site:ibiblio.org tibet
at .com I get only 688 and at .cn I get 1,140!
I do get different result orders.
When I add mongol as in site:ibiblio.org tibet mongol, at .cn I get 63 including one that reads:

Mongol-Tibet.Net is intended to cover things commonly related to the Mongol and Tibetan nations, people who are closely connected to each other, in many ways, along their history . There are some subsites which are on separate topics but are related to the main topic of this site. You will also find information on some other regions and people, especially the ones from Central Asia, who might somehow be related either to Mongolia or to Tibet. We would like to present certain concerns about the situations in Southern/Inner Mongolia and Tibet, whose people are suffering under the colonial rule of the People’s Republic of China. We would also like to provide information on the Uighur region, Burma and others.