Most of the time you see reports about UFOs, they're being spotted in some remote area that few people ever visit, or they're reported somewhere near Area 51. They're not usually found cruising down a river in Vietnam. According to the YouTuber, he'd seen the spacecraft in his dreams. In order to create the UFO's exterior, the YouTuber started by creating a mould out of sand. Among other things, he added windows, lighting, and even a set of powered doors to get in and out of the craft.