Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
van hanh » van thanh, ban hanh, van anh
hanh ca » hanh cac, hanh cat, hanh cua
duc van » duc va, duc tan, duc manh
ve pham » vi pham, v pham, ve phan
hieu ve » hieu va, hieu van
tang ma » mang may, tang van
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky
so sac » so sach, so dac

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sac ky ((nang xa) or (tang ma)) hoi. hieu ve pham duc van hanh ca ((cua triet) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sac ky ((nang xa) OR (tang ma)) hoi. hieu ve pham duc van hanh ca ((cua triet) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: so sac ky ((nang xa) or (tang ma)) hoi. hieu ve pham duc van hanh ca ((cua triet) or (va triet))*.