Peb muaj cov txheej txheem tsim khoom nruj heev, los ntawm kev sim mus rau warehouses.
Muab qhov kev txiav txim → npaj cov khoom siv raw (cov ntaub ntawv hauv paus) → kuaj → ntxiv cov khoom siv → ntshuam lub tshuab → ntsuas nruab nrab → paub meej → pressurize → pob → khw → nkoj
