Txij thaum ancient sij hawm, ib qho ntawm cov nyiam lauj kaub tais diav rau cov neeg laus thiab me nyuam yaus yog pob hau. Txawm li cas los xij, yuav kom lub pob ntseg tig tawm qab zib thiab muaj kua, koj yuav tsum ua raws li qee cov cai ntawm kev npaj. Tsis tas li ntawd, nws tseem yog ib qho tseem ceeb uas xaiv cov hom pob kws, uas tsim nyog rau ua noj ua haus.
