There are benefits to taking localbuses around Ho Chi Minh City, especially if you are an adventurous person and appreciate gliding around the city in air conditioned comfort. During heavy traffic periods, the bus can actually be faster as they have an informal right of way on the streets. Some of the city buses departing from Ben Thanh Market area do short looped runs between key sights of interest. Do your research first.
While schedules on the internet are written in Vietnamese only, there are colour-coded route maps that will at least give you a rough idea of the routes. A map of Saigon’s bus routes can be found at the Ben Thanh Bus Station but to be warned, it is more confusing than the London Tube map. There are numerous privately operated bus companies that run mid length routes to destinations outside Ho Chi Minh City.