Kev ua vaj tse pob zeb yog ib qho tseem ceeb ntawm kev tsim kho niaj hnub no, nrog rau kev siv ntau lub tshuab tshwj xeeb tsim los ua kom tau raws li qhov xav tau ntau lawm. Tshawb nrhiav ntau hom tshuab siv los ua cov pob zeb ua vaj tse, lawv cov yam ntxwv, bene
Cov pob zeb ua pob zeb yog cov khoom siv tseem ceeb hauv kev tsim kho kev lag luam thiab kev tsim cov blocks no yuav tsum tau siv cov tshuab tshwj xeeb xws li cov cement thaiv ua tshuab thiab thaiv cov tshuab xovxwm. Cov tshuab no ua lub luag haujlwm tseem ceeb hauv
Tseem muaj ntau hom tshuab cib nyob rau hauv kev ua lag luam, ntawm cov uas muaj lub tshuab cib hu ua pob zeb thaiv tshuab. Tab sis koj puas paub txog kev txheeb xyuas cov tshuab cib? Koj puas paub tias cov tsiaj ntawv nyob rau hauv lub cib tooj sawv cev rau dab tsi?