Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hang hai » hoang hai, hang tai, thanh hai
hanh hai » thanh hai, nhanh hai, hanh tai
su sach » so sach, vu sach
cau loc » hau loc, cau hoc, cau luc
van cau » van dau, van hau, van chat
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
cuu tre » cua tre, cau tren, cau treo
loc va » hoc va, luc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((nang xa) or (nang ma)) hoi. hieu van cau loc va ((hanh hai) or (hang hai)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang xa) OR (nang ma)) hoi. hieu van cau loc va ((hanh hai) OR (hang hai)) cuu tre.
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang xa) or (nang ma)) hoi. hieu van cau loc va ((hanh hai) or (hang hai)) cuu tre*.