Perhaps you should try some spelling variations:
dieu cua » dieu tra
van hanh » van thanh, ban hanh, van anh
luc van » luoc van, luu van, duc van
hieu ve » hieu va, hieu van
cac luc » cau luc, coc luc, cac nuoc
te cua » tue cua, le cua, de cua
te sac » te sach, te cac, te san
sac ky » cac ky, sai ky
ma hoi » mai hoi, ma hoa, me hoi
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 sac ky nang ((ma hoi) OR (xa hoi)). hieu ve cac luc van hanh ((dieu cua) or (te cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky nang ((ma hoi) OR (xa hoi)). hieu ve cac luc van hanh ((dieu cua) OR (te cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky nang ((ma hoi) OR (xa hoi)). hieu ve cac luc van hanh ((dieu cua) or (te cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te sac ky nang ((ma hoi) OR (xa hoi)). hieu ve cac luc van hanh ((dieu cua) or (te cua)) tre*.