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
dinh tri » chinh tri
dua tren » dung tren
cau treo » cau theo, cau tren, cau triet
su sach » so sach, vu sach
bang xa » lang xa, bang va, mang xa
van cau » van dau, van hau, van chat
truc va » thuc va, thuc vat, trung va
va dinh » van dinh, va kinh, va tinh

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 thien bang xa hoi. hieu van cau truc va dinh tri ((dua tren) OR (cau treo))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thien bang xa hoi. hieu van cau truc va dinh tri ((dua tren) OR (cau treo))".
• Adding a wildcard symbol may retrieve word variants: su sach thien bang xa hoi. hieu van cau truc va dinh tri ((dua tren) OR (cau treo))*.