Ntuj Hloov Tej huab cua tsis zoo nyob saum nruab ntug yog dab tsi ? Thiab ua mob rau peb lub cev tau li cas? Tej huab cua tsis zoo nyob saum nruab ntug yog dab tsi ? Thiab ua mob rau peb lub cev tau li cas ? (What is air pollution and how does it lead to disease in our bodies?)
Lub Koom Txoos Thaib tsuj xeeb txwm ib xyoos ntawm Vaj Qhia Les Os 14, thiab teeb tsa tus Tswv Qhia tshiab kav lub Cheeb Koom Txoos Tseej Maim
