A Vietnam-born, France- and U.S.-educated aeronautical engineer and physicist, Nguyen Vo made his directorial debut in 2006 with “The Buffalo Boy,” which toured numerous festivals. Though that film was set during Vietnam’s French colonial period and movingly depicts a father-son/mentor-disciple relationship, its elemental lyricism still resonates with “2030’s” depiction of a couple leading a frugal yet Edenic existence on their floating habitat. This time, the drama (adapted from Nguyen Ngoc Tu’s short story “Nuoc nhu nuoc mat”) is enriched by its focus on a sensuous and plucky female character who doesn’t buckle under intimidation or social ostracism in her pursuit of love and truth.