Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, thien van, lieu va
hanh hai » thanh hai, nhanh hai, hanh tai
hang hai » hoang hai, hang tai, thanh hai
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
van cau » van dau, van hau, van chat
truc va » thuc va, trung va
cuu tre » cua tre, cau tren, cau treo

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

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