Ecological sib. Kev ntim khoom yog rov ua dua tshiab, hloov mus ua kua ntses, lossis cia li yaj
Cov kws tshawb fawb ntsib txoj haujlwm tseem ceeb: tsim kom muaj kev sib raug zoo rau ib puag ncig, thaum zam cov yas thiab lwm yam khoom siv roj av, ...