Yuav ua li cas rov qab ib qho cim tawm ntawm 20 thiab nkag siab txog kev hloov pauv ntawm cov cim rau hauv qhov system tawm ntawm 20?
Nqa Rov Qab A Qib Tawm Ntawm 20: Koj puas tau xav paub yuav ua li cas cov qhab nia tau hauv tsev kawm tau hloov mus rau hauv ...