Cov khoom no yog lub log siv rau ntawm tes thawb tshuaj, muaj ntau yam cuam tshuam. Thiab muaj ntau cov ntaub ntawv siv rau lub log, qhov no siv yog PU, cov khoom siv no muaj qhov muaj zog, ntau lub teeb, tuaj yeem txuag kev siv hluav taws xob; muaj cov nyhuv kev poob siab. Muaj zog tuav, tsawg dua li yuav plam, txhim kho kev tsav tsheb ruaj khov, kev hloov chaw ua haujlwm tau yooj yim, tsim nyog rau cov haujlwm tshwj xeeb.
Cim npe nrov: Cov log siv PU khoom siv nrog xim daj, Tuam Tshoj log siv cov khoom siv pu nrog cov xim xim xim, Hoobkas