I haven't spent much time in Vietnam, but I knew this name long before I left the USA for Southeast Asia. Perhaps the equivalent of this name in the USA is "Smith," of which probably is the most common family name, but it has no connection to royalty, and instead I think it comes from the word "blacksmith," those who were iron workers of the past.
My stepdad's name is "Bob Smith," a combination of one of the most common family names and given names. We have stayed in hotels in Las Vegas where as many as 40 people in one hotel shared the same name.
the name Smith is very famous through the movie "Mr and mrs. Smith", right? It's good to know this information. thanks for sharing. I think each country has a "national family name" like that. That is interesting to know the story behind them.