Perhaps you should try some spelling variations:
luoc can » luc canh, hoc can, luoc dai
va triet » va thiet, va trien, ve triet
cao hoi » cau hoi, co hoi, cao hoc
hieu ve » hieu va, hieu van
duc van » duc va, duc tan, duc manh
te sac » te sach, te cac
te san » te ban, ke san, tu san
ve cac » va cac, vien cac
vi va » vi van, vai va, vu va

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) OR (te san)) ky nang cao hoi. hieu ve cac ((duc van) or (luoc can)) hanh vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sac) OR (te san)) ky nang cao hoi. hieu ve cac ((duc van) OR (luoc can)) hanh vi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sac) OR (te san)) ky nang cao hoi. hieu ve cac ((duc van) or (luoc can)) hanh vi va triet".
• Adding a wildcard symbol may retrieve word variants: ((te sac) OR (te san)) ky nang cao hoi. hieu ve cac ((duc van) or (luoc can)) hanh vi va triet*.