Tsev / Cov khoom cim npe “ultrasonic” Default sorting Tsi yog tej chaw Tsi yog qhov tseeb Tsi yog nqe: tsis rau siab Tsi yog nqe: yuav tsis tshua muaj ultrasonic welding ntaub tshuab Rau nonwoven npuag vuamTiv tauj peb