Perhaps you should try some spelling variations:
sach thue » sach thieu, sach tham, cach thuc
cam truc » cau truc, nam truc, lam truoc
van khai » van hai, van khi, dan khai
hieu van » hieu va, thien van, lieu va
sach thu » sach thieu, sach tham, cach thuc
dan hai » doan hai, dang hai, dan khai
van cam » van nam, van lam, van cau
truc va » thuc va, thuc vat, trung va
nang xa » nang x, lang xa, nang ma
cua tre » cua te, cuu tre, cua triet

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 thu) or (sach thue)) nang xa hoi. hieu van cam truc va ((dan hai) or (van khai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach thu) OR (sach thue)) nang xa hoi. hieu van cam truc va ((dan hai) OR (van khai)) cua tre.
• Adding a wildcard symbol may retrieve word variants: thu ((sach thu) or (sach thue)) nang xa hoi. hieu van cam truc va ((dan hai) or (van khai)) cua tre*.