Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thien bang » khien bang, thien ban, thien dang
hieu van » hieu va, thien van, lieu va
dua tren » dung tren
so sach » so sanh, bo sach, co sach
bang xa » lang xa, bang va, mang xa
van cau » van dau, van hau, van chat
cau tuc » cau truc, cau tu, cau luc
va dinh » van dinh, va kinh, va tinh
dinh ve » dinh ket, dinh van
cuu tre » cua tre, cau tren, cau treo
tuc va » thuc va, truc va, tuc xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach thien bang xa hoi. hieu van cau tuc va dinh ve ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach thien bang xa hoi. hieu van cau tuc va dinh ve ((dua tren) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: so sach thien bang xa hoi. hieu van cau tuc va dinh ve ((dua tren) or (cuu tre))*.