Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
mang xa » mang may, dang xay, mang cua
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
cac luc » cau luc, coc luc, cac nuoc
luc van » luoc van, luu van, duc van
tai ky » thai ky, trai ky, sai ky
te cua » tue cua, le cua
de cua » le cua, dieu cua
ve cac » va cac, vien cac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te tai ky ((mang xa) or (lang xa)) hoi. hieu ve cac luc van hanh ((de cua) or (te cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te tai ky ((mang xa) OR (lang xa)) hoi. hieu ve cac luc van hanh ((de cua) OR (te cua)) te.
• Adding a wildcard symbol may retrieve word variants: te tai ky ((mang xa) or (lang xa)) hoi. hieu ve cac luc van hanh ((de cua) or (te cua)) te*.