Perhaps you should try some spelling variations:
hang hai » hoang hai, hang tai, thanh hai
so sach » so sanh, bo sach, co sach
hai cua » thai cua, dai cua, hoi cua
duc van » duc va, duc tan, duc manh
duc ban » duc tan, dua ban, duc man
cua tre » cua te, cuu tre, cua triet
nang xa » lang xa, nang ma, mang xa
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach y ((nang xa) or (nang x)) hoi. hieu va cam ((duc ban) or (duc van)) hang hai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y ((nang xa) OR (nang x)) hoi. hieu va cam ((duc ban) OR (duc van)) hang hai cua tre.
• Adding a wildcard symbol may retrieve word variants: so sach y ((nang xa) or (nang x)) hoi. hieu va cam ((duc ban) or (duc van)) hang hai cua tre*.