ntsia thawv ua tshuab machinery nyob rau hauv tus txheej txheem ntawm kev siv, nws yog inevitable uas yuav muaj xws li thiab tej teeb meem. Thaum cov ntsia hlau ua tshuab teeb meem, nws yuav cuam tshuam rau kev tsim khoom ib txwm, yog tias peb xav kom cov ntsia hlau zoo, ces peb yuav tsum tau ua tus qauv ntawm d ...
Nyeem ntxiv