Muaj 4 qhov laj thawj:
ib qho yog tus cwj mem: xyuas seb nws puas yog tus cwj mem hloov thermal. Tus cwj mem zoo tib yam tsis tau txais.
Qhov thib ob yog txheej txheej: Tshawb xyuas seb puas muaj subliamtion txheej sab nraud ntawm lub khob.
Qhov thib peb: Tshawb xyuas seb puas yog qhov ntsuas kub thiab lub sijhawm?
Tom ntej: Txheeb xyuas seb puas siv cov ntawv sublimation, cov ntawv ib txwm siv tsis tau
