Perhaps you should try some spelling variations:
va triet » va trien, ve triet, cua triet
nam thuc » nam thuoc, am thuc, nam thu
su sach » so sach, vu sach
hanh va » hang va, hanh vi
lo nang » ho nang, ly nang, loai nang
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu van
hieu va » lieu va, hieu qua
sach lo » sach dao, sach doi, sach hoi
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
thiet » thieu

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 lo nang ma hoa. ((hieu ve) or (hieu va)) nam thuc va hanh va ((va triet) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach lo nang ma hoa. ((hieu ve) OR (hieu va)) nam thuc va hanh va ((va triet) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: su sach lo nang ma hoa. ((hieu ve) or (hieu va)) nam thuc va hanh va ((va triet) or (va thiet))*.