Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
nam thuc » nam thuoc, am thuc, nam thu
cam thuc » am thuc, cam thu, can thuc
va hanh » van hanh, va thanh, va danh
su sach » so sach, vu sach
sach va » sach xa, sach ha, sach dao
hieu ve » hieu va, hieu van
cao hoi » cau hoi, co hoi, cao hoc
va nang » van nang, da nang, cam nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach va nang cao hoi. hieu ve ((cam thuc) or (nam thuc)) va hanh vi ((cua triet) OR (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach va nang cao hoi. hieu ve ((cam thuc) OR (nam thuc)) va hanh vi ((cua triet) OR (va triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach va nang cao hoi. hieu ve ((cam thuc) or (nam thuc)) va hanh vi ((cua triet) OR (va triet))".
• Adding a wildcard symbol may retrieve word variants: su sach va nang cao hoi. hieu ve ((cam thuc) or (nam thuc)) va hanh vi ((cua triet) OR (va triet))*.