Cov qhov rooj hluav taws tsis cuam tshuam qhov tseem ceeb ntawm cov qauv tsim thiab qee cov qauv kos duab zoo li lwm yam khoom, thiab tuaj yeem ua lub luag haujlwm zoo hauv kev tiv thaiv hluav taws thaum muaj hluav taws kub thiab lwm yam xwm txheej. Ntau tus neeg dim ntawm qhov hluav taws kub vim qhov hluav taws kub qhov rooj nres qhov hluav taws kub tsis txhob sib kis.