Ntawv Sau "Khoom lag luam" tshwj xeeb hauv kev ua haujlwm sab hauv. Raws li lub ntsiab lus “zoo ntoo ua lag luam” lub tuam txhab paub txog cov phiaj xwm tshwj xeeb hauv vaj tse. Lub chaw zov me nyuam yog ua kom tau raws li qhov kev thov no. Tus qauv txo tab sis kev ua si tau pom tau siv cov xim sib xyaw tshwj xeeb. Cov ntawv sau tau nthuav tawm lub chaw ruaj khov thiab nws lub tswv yim siv tsuas yog cov khoom siv uas muaj txiaj ntsig tshaj plaws: Cov ntawv yog ua los ntawm cov paj rwb 100 feem pua, hnab ntawv ntawm cov ntoo veneer tiag. Daim npav ua lag luam “koom nrog” cov lus cog tseg ntawm cov tuam txhab los ntawm tsim cov chav 3-seem uas muaj cov khoom lag luam ntoo.