Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
nam thuc » nam thuoc, am thuc, nam thu
hieu van » thien van, lieu va, hieu ve
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
tu sach » thu sach, su sach, te sach

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y ((nang xa) or (nang ma)) hoi. ((hieu van) or (hieu va)) nam thuc va hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y ((nang xa) OR (nang ma)) hoi. ((hieu van) OR (hieu va)) nam thuc va hanh va su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach y ((nang xa) or (nang ma)) hoi. ((hieu van) or (hieu va)) nam thuc va hanh va su triet*.