Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
su sach » so sach, vu sach
te sach » toc sach
nang xa » lang xa, nang ma, mang xa
dao duc » giao duc, tao duoc
va cua » va chua, via cua, ca cua
dan va » doan va, dan ca, ban va
va dan » ca dan, va dao, va dau
cua te » cua tu

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) or (te sach)) tru ((nang xa) OR (nang x)) hoi. hieu van dao duc va dan va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (te sach)) tru ((nang xa) OR (nang x)) hoi. hieu van dao duc va dan va cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (te sach)) tru ((nang xa) OR (nang x)) hoi. hieu van dao duc va dan va cua te".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (te sach)) tru ((nang xa) OR (nang x)) hoi. hieu van dao duc va dan va cua te*.