Ib qho kev daws teeb meem rau cov phiaj xwm hnyav cia, kev hloov pauv me me kom haum rau txoj haujlwm hloov pauv thaum muaj ntau hom phaus phiaj. Ua tsaug rau DHZ cov khoom siv haib thiab ntau lawm, qauv qauv ntawm cov khoom siv ruaj khov thiab muaj tsib-xyoo lav.