Kev siv lub tshuab txhaj tshuaj ntsia hlau, qhov zoo tshaj plaws ntawm lub hau ntswj, qhov ua kom muaj ntsia hlau
Mar 23, 2020
Qhov ntsuas kub tsis tshua muaj siab thaum cov ntaub ntawv raw.
② Cov khoom siv hlau txawv teb chaws tau sib xyaw rau hauv cov khoom nyoos lossis muaj ntau cov khoom tsis haum ntawm cov khoom siv raw.
Cov ntsia hlau kaw thaum lub sijhawm ntev dhau lawm.
Qhov kev xaiv ntawm cov khoom siv rau kev tsim cov ntsia hlau tsis tsim nyog.
⑤ Tsawg ntsia hlau tsim qhov raug thiab tsawg kub kho hardness ntawm xov ua hauj lwm nto.
