Perhaps you should try some spelling variations:
trong van » trong cac
vu khach » vu khanh, vu khac, vay khach
khach ty » sach ty
su triet » su tien, ve triet
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
va tinh » may tinh
tinh vi » trinh vi, tinh voi, tinh va
su viet » so viet

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu khach ty ((trong van) or (mang may)) hoi. hieu ve pham duc va tinh vi ((su triet) OR (su viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu khach ty ((trong van) OR (mang may)) hoi. hieu ve pham duc va tinh vi ((su triet) OR (su viet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu khach ty ((trong van) or (mang may)) hoi. hieu ve pham duc va tinh vi ((su triet) OR (su viet))".
• Adding a wildcard symbol may retrieve word variants: vu khach ty ((trong van) or (mang may)) hoi. hieu ve pham duc va tinh vi ((su triet) OR (su viet))*.