Perhaps you should try some spelling variations:
thu sac » thu sach, thu san, thu xac
va hanh » van hanh, va thanh, ban hanh
hai cua » thai cua, dai cua, hoi cua
va danh » va dinh, va dan, dia danh
cac bao » cach bao, cac bai, cac ban
hieu va » lieu va
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sac ky nang x hoi. ((hieu va) or (hieu qua)) cac bao ((va hanh) OR (va danh)) hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sac ky nang x hoi. ((hieu va) OR (hieu qua)) cac bao ((va hanh) OR (va danh)) hai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sac ky nang x hoi. ((hieu va) or (hieu qua)) cac bao ((va hanh) OR (va danh)) hai cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sac ky nang x hoi. ((hieu va) or (hieu qua)) cac bao ((va hanh) OR (va danh)) hai cua tre*.