Vietnamese basically celebrate the festivals that are linked to Lord Buddha for example the natives celebrate Buddha's birthday. People visit temples and worship Lord Buddha and ask for more strength to overcome their problems. The temples are lit with candles and monks are served by the devotees to seek their blessings.
Other important festivals that are celebrated with fun and gaiety are the Mid Autumn Festival and the Lunar Year in which grand proceedings are taken out and people go out and celebrate such auspicious events with each other and give gifts to each other.