Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
danh hai » dang hai, lanh hai, manh hai
quoc ban » quoc bao, quoc lan, quoc quan
hai cua » thai cua, dai cua, hoi cua
duc van » duc va, duc tan, duc manh
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
tang ma » tang van
va lam » van lam, va lap

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach y ((tang ma) or (mang may)) hoi. hieu va lam ((quoc ban) or (duc van)) danh hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach y ((tang ma) OR (mang may)) hoi. hieu va lam ((quoc ban) OR (duc van)) danh hai cua tre.
• Adding a wildcard symbol may retrieve word variants: thuat sach y ((tang ma) or (mang may)) hoi. hieu va lam ((quoc ban) or (duc van)) danh hai cua tre*.