HARBIN, May 18 (Xinhua) -- The 10th China-Russia Expo, themed "Trust, Cooperation, and Mutual Benefit," opened in Harbin, northeast China's Heilongjiang Province, on Sunday. It is jointly hosted by the Ministry of Commerce of the People's Republic of China, the People's Government of Heilongjiang Province, the Ministry of Economic Development of the Russian Federation, and the Ministry of Industry and Trade of the Russian Federation.