Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
khoa hoi » khoan hoi, khoa hoc, khoa noi
khoa doi » hoa doi, khoa noi, khoan hoi
va hanh » van hanh, va thanh, ban hanh
va danh » va dinh, va dan, dia danh
cao xuc » cam xuc, cao duc, cao suc
sach ky » sac ky, sach y, sach ty
qua cao » qua cac, qua ca, qua cai
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ky dang ((khoa hoi) OR (khoa doi)). hieu qua cao xuc ((va hanh) or (va danh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky dang ((khoa hoi) OR (khoa doi)). hieu qua cao xuc ((va hanh) OR (va danh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky dang ((khoa hoi) OR (khoa doi)). hieu qua cao xuc ((va hanh) or (va danh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky dang ((khoa hoi) OR (khoa doi)). hieu qua cao xuc ((va hanh) or (va danh)) vi cua tre*.