Perhaps you should try some spelling variations:
nam thuc » nam thuoc, am thuc, nam thu
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
sach ty » sach y, sach tu, sach thu
su sach » so sach, vu sach
sang ma » tang ma, nang ma, sang tao
hieu ve » hieu va, hieu van
ve nam » he nam, va nam, le nam
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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 ty ((sang ma) or (mang may)) hoi. hieu ve nam thuc va hanh ((vi cua) OR (di cua)) viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((sang ma) OR (mang may)) hoi. hieu ve nam thuc va hanh ((vi cua) OR (di cua)) viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((sang ma) or (mang may)) hoi. hieu ve nam thuc va hanh ((vi cua) OR (di cua)) viet*".