Hnub no, txawm hais tias kev siv thev naus laus zis nce qib, tib neeg tseem yuav tsum tau sau los ntawm tes. Ua ntej tshaj plaws, qhov no siv rau cov menyuam kawm ntawv thiab cov tub ntxhais kawm uas raug yuam kom sau ntawv hauv cov lus qhuab qhia, sau ntawv thiab nthuav qhia, thiab xeem. Yuav ua li cas kawm sau ntawv sai sai kom cov ntawv sau tau yooj yim disassembled? Cov lus qhia hauv qab no yuav pab koj txhim kho koj txoj kev sau ntawv nrawm tsis muaj sijhawm