Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
sach tham » sach nha
cua viet » ca viet, hoa viet, cua vat
hanh vai » hanh vi, hanh va, hanh tai
vai cua » dai cua, hai cua, lai cua
va hanh » van hanh, va thanh, va danh
sach ty » sach y, sach tu, sach thu
may hoi » may thoi, tay hoi, mai hoi
hieu ve » hieu va, hieu van
thuc » thu

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) or (sach tham)) mang may hoi. hieu ve ((am thuc) or (nam thuoc)) va hanh vai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach tham)) mang may hoi. hieu ve ((am thuc) OR (nam thuoc)) va hanh vai cua viet.
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach tham)) mang may hoi. hieu ve ((am thuc) or (nam thuoc)) va hanh vai cua viet*.