“Rich Hill,” a new documentary about three boys and their families struggling to make ends meet in a small Missouri town, started screening at the Sundance Film Festival this week. The film, beautifully shot, explores rural poverty and hopes for better lives. Andrew, one of the boys, says times are tough, but he has hope. “This is what goes through my mind: God has to be busy with everyone else. Eventually he will come into my life and help me. I hope that happens. It’s going to break my heart if it don’t.” The filmmakers, cousins with ties to Rich Hill, Missouri, are trying to organize screenings of the movie near the town.