Beijing tshiab tshav dav hlau kev ruaj ntseg puag pej xeem cov tsev nyob

Kev muab khoom thiab kev teeb tsa cov khoom siv hnub ci zog rau thawj theem ntawm pej xeem cov tsev xauj tsev project rau cov txuj ci hauv lub tshav dav hlau tshiab Beijing lub neej txhawb nqa