Perhaps you should try some spelling variations:
cau treo » cau theo, cau tren, cau triet
hieu van » hieu va, thien van, lieu va
manh hai » lanh hai, minh hai, thanh hai
hai cau » hai chau, hai chu, hai hau
truc va » thuc va, thuc vat, trung va
nang xa » nang x, lang xa, nang ma
van cam » van nam, van lam, van cau
sach v » sach va, sach y, sach vay
tuc va » thuc va, tuc xa, duc va
sach 2 » sach y

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 v) or (sach 2)) nang xa hoi. hieu van cam ((tuc va) OR (truc va)) manh hai cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach v) OR (sach 2)) nang xa hoi. hieu van cam ((tuc va) OR (truc va)) manh hai cau treo.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach v) or (sach 2)) nang xa hoi. hieu van cam ((tuc va) OR (truc va)) manh hai cau treo".
• Adding a wildcard symbol may retrieve word variants: su ((sach v) or (sach 2)) nang xa hoi. hieu van cam ((tuc va) OR (truc va)) manh hai cau treo*.