The French definitely lost in Vietnam, first to the Japanese, then after the war to the Viet Minh. Ho had support of every major power, including America, when he was mobilising his troops against the Japs, and after the war, the French were given back Vietnam. Ho and the French didn't make suitable terms, and the French weren't behaving acceptably, so the war started against France, and lasted for 10 years. America then took the war up against the spread of communism, not in the pursuit of new lands. Many of the Japs that Ho's forces fought against, stayed and fought with Ho against the French, although, I'm not sure whether they were still around when war started against the Americans.
There is lots you can read on the Vietnam war, and Netflix have got a couple of series that are worth watching, but to say any side won, is a bit of a stretch, although, communism could be slated as the real winner, and the French the real loser.
