Perhaps you should try some spelling variations:
tang van » dang van, hoang van, trong van
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
vat hanh » vat thanh, van hanh, va hanh
so sach » so sanh, bo sach, co sach
sach ky » sac ky, sach y, sach ty
tang ma » mang may
hieu ve » hieu va
vi hoa » voi hoa, vi hoc, va hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ky ((tang ma) or (tang van)) hoi. ((hieu ve) or (hieu van)) nam thuc vat hanh vi hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky ((tang ma) OR (tang van)) hoi. ((hieu ve) OR (hieu van)) nam thuc vat hanh vi hoa viet.
• Adding a wildcard symbol may retrieve word variants: so sach ky ((tang ma) or (tang van)) hoi. ((hieu ve) or (hieu van)) nam thuc vat hanh vi hoa viet*.