Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thien lang » thien bang, thien dang, thien nang
dua tren » dung tren
su sach » so sach, vu sach
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
lang xa » lang ha, dang xay, lang 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: su sach thien lang xa hoi. hieu ((van lam) OR (van nam)) tuc va hanh va ((dua tren) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thien lang xa hoi. hieu ((van lam) OR (van nam)) tuc va hanh va ((dua tren) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thien lang xa hoi. hieu ((van lam) OR (van nam)) tuc va hanh va ((dua tren) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: su sach thien lang xa hoi. hieu ((van lam) OR (van nam)) tuc va hanh va ((dua tren) or (cuu tre))*.