Lub qhov rooj tua hluav taws yog cov khoom siv hluav taws xob. Kev ua haujlwm txhua hnub yog qhov yooj yim heev. Nias lub nce, nqis thiab nres cov nyees khawm ntawm lub thawv tswj kom tswj kev nce thiab nqis ntawm lub qhov rooj tua hluav taws. Thaum tau txais lub tswb ceeb toom hluav taws, lub qhov rooj kaw hluav taws yuav nqis los sai sai los tiv thaiv qhov hluav taws kub ntawm qhov hluav taws kub uas nyob ib sab, thiab ua lub luag haujlwm ntawm kev sib cais thiab tiv thaiv kev sib kis.