china actually "secretly" (or openly secretly) adopted capitalist ideals for it's planned economy (such as opening up foreign investments and exports of cheap labour) - see https://en.wikipedia.org/wiki/Deng_Xiaoping (and slightly better article https://en.wikipedia.org/wiki/Socialism_with_Chinese_charact...). These reforms have single-handedly made china the world's 2nd biggest, economy after the US.

Venezuela doesn't have the same level of labour exporting, and relied on natural resources, and even actively nationalized private businesses (against the interests of foreign investors). Obviously they are going to stop getting investment, and as oil prices tanked, their socialist policies (or, bribery of the voters with "free" stuff) can't be kept up.