Perhaps you should try some spelling variations:
cay thuoc » cua thuoc, nam thuoc, va thuoc
cua viet » ca viet, hoa viet, cua vat
van hanh » van thanh, ban hanh, van anh
hieu van » hieu va, thien van, lieu va
thu sach » thuat sach, thuoc sach, thu hoach
van cay » van cau, van bay, van ca
nang ma » tang ma, sang ma, nang cao
va hanh » va thanh, va danh, ban hanh
tu sach » su sach, te sach, tu cach
ma hoi » mai hoi, xa hoi, ma hoa

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) or (thu sach)) ky nang ma hoi. hieu van cay thuoc ((va hanh) or (van hanh)) dai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang ma hoi. hieu van cay thuoc ((va hanh) OR (van hanh)) dai cua viet.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky nang ma hoi. hieu van cay thuoc ((va hanh) or (van hanh)) dai cua viet*.