Lub lens

Cov log tsheb ciav hlau yog qhov tseem ceeb los xyuas kom meej tias kev ua haujlwm ntawm cov tsheb ciav hlau muaj kev nyab xeeb. Hauv cov txheej txheem ntawm kev ua tiav xoom-qhov tsis zoo, cov chaw tsim khoom siv tsheb ciav hlau yuav tsum tswj hwm txhua kauj ruam ntawm cov txheej txheem ntau lawm, thiab cov kab nkhaus nias-haum tso zis los ntawm lub tshuab teeb tsa log yog qhov qhia tseem ceeb ntawm qhov zoo ntawm kev sib dhos log. Cov ntawv thov tseem ceeb ntawm cov khoom no yog nyob rau hauv thaj chaw ntawm kev teeb pom kev zoo thiab kev tshuaj xyuas.