Perhaps you should try some spelling variations:
thieu xang » thieu khang, thieu quang, chieu sang
hieu van » hieu va, thien van, lieu va
van bac » van ban, van bao, van hac
so sach » bo sach, co sach, hoc sach
xang xa » lang xa, mang xa, ang xa
so sanh » do sanh
cua tre » cua te, cuu tre, cua triet
xac va » tac va, ac va, bac va
loc va » hoc va, luc va
vi cua » vai cua, di cua

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) OR (so sanh)) thieu xang xa hoi. hieu van bac ((xac va) or (loc va)) hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (so sanh)) thieu xang xa hoi. hieu van bac ((xac va) OR (loc va)) hanh vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) OR (so sanh)) thieu xang xa hoi. hieu van bac ((xac va) or (loc va)) hanh vi cua tre*".