Nam Du is a small archipelago (near Phu Quoc island) of Kien Giang (a province in Mekong Delta). The largest island is Hon Lon (Large Islet), locally called Cu Tron islet. Nam Du tourism is at its early stage so everything is still pristine and natural. Following are some my informations and experiences for travelling to Nam Du island.
How to get to to Nam Du island
Basically, way to get Nam Du is similar to Phu Quoc. You have to get to Rach Gia from Ho Chi Minh by bus (take about 6 hours) then take the boat.