A communist society, is a society in the absence of a state, without social class, and with no mechanism for the maintenance, transfer or acquisition of private capital.
So that I am not mistaken, I will define each of those three things below.
- State: Any institution or person with a claim to monopoly of force in any given territory
- Social class: A division of access, power, status or other privilege that define different groups of people within a society.
- Private Capital: Resources held by an individual that can be used to wield political authority of others in the form of productive means or access to goods and services.
All the above being understood it should be clear to you that neither china, nor Russia, Cube, Venezuela, Vietnam nor North Korea are in any way communist. The only connection these nations have to Communism is that the dictatorial class which controls these countries uses the brand of communism to justify its reign. This is not unlike the oligarchy which dominates the USA and Russia who dangle the potential of being a millionaire as a carrot to there workers so that they can continue to exploit them for there own personal gain.