Siv dav hauv cov khoom xws li lub plhaub thiab cov khoom sab hauv ntawm cov khoom siv hauv tsev thiab cov khoom siv hluav taws xob, cov khoom ntim khoom noj xws li cov khoom siv pov tseg xws li khob dej haus thiab cov khoom ntim mis nyuj, thiab ntau yam kev txhaj tshuaj molding suav nrog cov khoom siv hauv chaw ua haujlwm, cov khoom siv hauv chav ua noj, cov khoom siv da dej, thiab cov khoom ua si, thiab lwm yam.
