Uh, neither China nor Vietnam are socialist. They have socialist polices and programs, just like every other country in the world, but they aren't socialist countries.

China is a hybrid of capitalist dictatorship with elements of socialism and communism. Their massive effort in directly owning a piece of every company that originated in China, then using that to enforce state-decided policies is a direct contradiction to the theory of socialism. In fact I challenge you to please show me what exactly the workers own or influence in China. I argue that it's virtually nothing.

Vietnam is so far down the socialist rabbit hole that they are communist. As evidenced by their one political party being titled The Communist Party of Vietnam. They based their ideology on Marx and Lenin for decades. However, since about the late 90's when they saw an opportunity for massive growth like China, they did the same thing as China and started muddying the waters and became an amalgamation of a bunch of different political and economic theories after capitalism began wearing down what they thought was iron-clad ideology.