Merics is a great site for information on China, and this article has many factoids to review the relationship between China and Russia. I find this interesting and pertinent. I recommend you visit the site and review the China-Russia Dashboard. All IMO.
https://merics.org/en/china-russia-dashboard-facts-and-figures-special-relationship
“Sino-Russian relations are closer today than they have been in decades. In these times of historic geopolitical tensions, it is all the more important to understand the nature and elements of the relationship of two of the world’s most influential powers. This dashboard aims to contribute to a better understanding by tracking and analyzing the economic, political, security, and societal dimensions of China-Russia relations and their changing quality over time. It is a collaborative research effort of the Centre for Eastern Studies (OSW), the Mercator Institute for China Studies (MERICS), and the Swedish National China Centre (NKK) and Stockholm Centre for EasternEuropean Studies (SCEEUS) at the Swedish Institute of International Affairs (UI).”