Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thien ban » thien bang, thien van, phien ban
cau tren » cu tren, dau tren, ca tren
cau treo » cau theo, cau triet, cau trieu
hieu van » hieu va, thien van, lieu va
dua tren » dung tren
dinh vi » dinh ve, dinh viet, dinh tri
su sach » so sach, vu sach
truc va » thuc va, thuc vat, trung va
van cau » van dau, van hau, van chat
va dinh » van dinh, va kinh, va tinh
ban xa » ban va, ban ma, ban da

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