1. Ntxuav txhua nkawm thom khwm ncaws pob los ntawm tes los yog muab tso rau hauv lub hnab ntxhua khaub ncaws ua ntej muab tso rau hauv lub tshuab ntxhua khaub ncaws.
2. Siv dej txias thiab tshuaj ntxuav me me (zoo dua yog ib qho tsim los rau cov ntaub mos muag) thaum ntxuav koj cov thom khwm ncaws pob.
3. Nco ntsoov yuav cov thom khwm zoo nrog cov ntaub ntub dej. Cov ntaub ntawv no pab ua kom koj txhais taw qhuav thiab xis nyob thaum koj ua haujlwm tawm.
4. Yog tias koj ntxuav cov thom khwm wool, siv cov ntaub plaub tshwj xeeb ntxuav, thiab tsis txhob wringing thiab twisting.
5. Cua qhuav koj cov thom khwm ncaws pob es tsis muab tso rau hauv lub tshuab ziab khaub ncaws. Qhov no yuav pab kom cov elasticity ntawm cov ntaub thiab khaws cov duab ntawm lub thom khwm.
6. Yog tias koj ob txhais taw nyiam tawm hws ntau thaum lub sijhawm ua haujlwm, xav txog kev yuav ob peb nkawm thom khwm hloov ntawm lub sijhawm koj ua si lossis sim cov thom khwm tsis muaj dej. Qhov no yuav pab kom koj ob txhais taw xis nyob thiab qhuav.