Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
danh dai » danh dau, danh di, danh sai
tang ma » mang may, tang van
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
va danh » va dinh, va dan, va hanh
nang ma » sang ma, nang cao, mang may
cua tre » cua te, cuu tre, cua triet

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 ky ((nang ma) OR (tang ma)) hoi. hieu ((van chat) or (cao chat)) thuc va danh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky ((nang ma) OR (tang ma)) hoi. hieu ((van chat) OR (cao chat)) thuc va danh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky ((nang ma) OR (tang ma)) hoi. hieu ((van chat) or (cao chat)) thuc va danh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ky ((nang ma) OR (tang ma)) hoi. hieu ((van chat) or (cao chat)) thuc va danh dai cua tre*.