Perhaps you should try some spelling variations:
thuoc vat » thuc vat, thuoc va, thuoc bat
nam thuoc » nam thuc, nam thu, nha thuoc
thu sach » tu sach, thuat sach, thuoc sach
vat hanh » vat thanh, van hanh, va hanh
hieu van » thien van, lieu va, hieu ve
tang ma » mang may, tang van
sach lo » sach dao, sach doi, sach hoi
hieu va » lieu va, hieu qua
nang ma » sang ma, nang cao, mang may
va viet » hoa viet, san viet, mai viet
vi va » vi van, vai va, vu va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach lo ((nang ma) OR (tang ma)) hoi. ((hieu van) or (hieu va)) nam thuoc vat hanh vi va viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach lo ((nang ma) OR (tang ma)) hoi. ((hieu van) OR (hieu va)) nam thuoc vat hanh vi va viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach lo ((nang ma) OR (tang ma)) hoi. ((hieu van) or (hieu va)) nam thuoc vat hanh vi va viet".
• Adding a wildcard symbol may retrieve word variants: thu sach lo ((nang ma) OR (tang ma)) hoi. ((hieu van) or (hieu va)) nam thuoc vat hanh vi va viet*.