Kev puas tsuaj ntawm vuam kev nyuaj siab ntawm qhov nruab nrab zaus qhov chaw vuam tshuab feem ntau yog siv rau hauv 6 yam: 1, vuam lub zog; 2, vuam nruj; 3, stability ntawm vuam qhov chaw; 4, kev ua haujlwm raug; 5, seem stability; 6. Corrosion kuj. Hauv qab no me me series rau koj los qhia ...
Nyeem ntxiv