Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
toc sach » hoc sach, doc sach, thuoc sach
dinh lam » dinh van, tinh lao
cac duc » cac du, cao duc, cac dac
cuu tre » cau tren, cau treo
va dinh » van dinh, va kinh, va tinh
van cac » van hac, van cau, van bac
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
cua tre » cua te, cua triet, dua tren

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (toc sach)) ky lang xa hoi. hieu van cac duc va dinh lam ((cuu tre) OR (cua tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky lang xa hoi. hieu van cac duc va dinh lam ((cuu tre) OR (cua tre))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) ky lang xa hoi. hieu van cac duc va dinh lam ((cuu tre) OR (cua tre))*".