Name of the round bamboo tool in Koho language (Krăngọ village)

Ma Ly says the name of the tool made of a thin slice of bamboo with both ends tied together. Because of the many inclusion in the clay, they are used really fast. The newest ones, more sharp, are use to thin the walls of the pots, while the ones that are already used, with blunt edges are used in the preforming of the bottom. These tools are now imitated in metal, but they still have the same name.