Cov cuab yeej tshiab kom tau raws li Cov Kev Sib Tw Tshiab
PVA 1799 suav nrog cov khoom siv tshwj xeeb uas tau tsim los siv cov thev naus laus zis los muab kev ua tau zoo tshwj xeeb hauv ntau yam kev tsim kho. Nws tau hais tias kom ua tau zoo dua nws cov neeg sib tw hauv kev ua lag luam, raws li nws ua raws li kev lag luam xav tau. Nws pab txhawm rau txhim kho qhov adhesion thiab yooj, ua rau nws yog ib qho khoom zoo rau cov kws tshaj lij uas xav tau kev ua haujlwm.