Cov hniav ntse

Cov hniav ntse

Cov hniav ntse tsis tas yuav tsum tau muab tshem tawm, tab sis lawv yuav tsum tau muab tshem tawm yog tias lawv rov ua dua, ua rau cov molars uas nyob ib sab, ua kom huv si (yuav ua rau cov hniav lwj), lossis ua rau cov hlwv.