Ua kom muaj cov ntaub ntawv siab ntawm cov khoom siv sib xyaw ua ke, tsim los ntawm kev ua kom qhuav lossis txias dua tshiab, cov tshuab hluav taws xob muaj ntau yam xws li kev ua kom siab, xeb tsis kam, puas yog kev ua tsis kam thiab rwb thaiv tsev.