When the old government was overthrown on April 30, 1975, the new government arrested anyone who had been part of the army. They sent all the people who were rich or owned businesses to move out of the cities and live out in the countryside. It was a rule of the new government.
Also, from 1975 to 1982 we didn't have enough food. We were used to having rice, meat, and vegetables for lunch and dinner (it was traditional), but at that time, we had to eat corn, sweet potatoes, and yams instead of rice.
And there weren't enough jobs in factories and businesses for people who wanted work so crime increased.
Since 1982 the situation has gotten better for many people because
relatives who went to the United States and got jobs have sent money back
so many factories, stores, and restaurants have opened in Vietnam.