Perhaps you should try some spelling variations:
thanh doi » thanh loi, thanh moi, thanh do
sach thu » sach thue, sach thieu, sach tham
doi cuu » doi cua, doi cuoc
cuu tre » cua tre, cau tren, cau treo
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
sach tu » cach tu, sach ty, sach uu
tuc va » thuc va, truc va, duc va
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: te ((sach thu) or (sach tu)) nang xa hoi. hieu va cam ((tuc va) OR (tuc xa)) thanh doi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach thu) OR (sach tu)) nang xa hoi. hieu va cam ((tuc va) OR (tuc xa)) thanh doi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach thu) or (sach tu)) nang xa hoi. hieu va cam ((tuc va) OR (tuc xa)) thanh doi cuu tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach thu) or (sach tu)) nang xa hoi. hieu va cam ((tuc va) OR (tuc xa)) thanh doi cuu tre*.