Muab qhov kev noj cov khob ntawv tsis tu ncua thiab cov khoom tsim tawm txhua hnub los ntawm cov tshuab tsim khoom, kev cia kom zoo yog qhov tseem ceeb los tswj kom zoo.
1. Cov khob ntawv yuav tsum tau ntim rau hauv cov thawv ntawv; tawm hauv lawv xoob exposes lawv yellowing thiab noo noo.
2. Cov khob yuav tsum muab tso rau hauv cov hnab yas tshwj xeeb uas kaw nruj nreem; raug huab cua tuaj yeem ua rau daim ntawv daj.
3. Khaws lub khob rau hauv qhov chaw qhuav kom tsis txhob ya raws kev puas tsuaj, thiab xyuas kom cov thawv ntawv ntim tau ruaj khov nrog daim kab xev.
4. Lub neej txee lub neej yog ib mus rau ob xyoos (muab lawv ntim khoom kom zoo); txwv tsis pub, nws feem ntau yog rau lub hlis.
