Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh vai » hanh vi, hanh va, hanh tai
vai cua » dai cua, hai cua, lai cua
hoc can » hoc dan, hoc cao, hoc cac
duc van » duc va, duc tan, duc manh
hieu ve » hieu va, hieu van
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
san ky » sang ky, van ky, dan ky
ve cac » va cac, vien cac
ke san » ke dan

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

• Performing a fuzzy search may retrieve terms with similar spellings: ke san ky ((sang ma) OR (nang ma)) hoi. hieu ve cac ((duc van) or (hoc can)) hanh vai cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ke san ky ((sang ma) OR (nang ma)) hoi. hieu ve cac ((duc van) OR (hoc can)) hanh vai cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ke san ky ((sang ma) OR (nang ma)) hoi. hieu ve cac ((duc van) or (hoc can)) hanh vai cua triet".
• Adding a wildcard symbol may retrieve word variants: ke san ky ((sang ma) OR (nang ma)) hoi. hieu ve cac ((duc van) or (hoc can)) hanh vai cua triet*.