Guohao cua lim 17801-31090 muab ntau yam khoom siv lim kom tau raws li qhov xav tau ntawm cov qauv tsheb sib txawv thiab cov khoom siv. Txawm hais tias nws yog tsheb, tsheb thauj khoom, lossis kev tsim kho tshuab, cov khoom lim tsim nyog tuaj yeem pom.