Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh di » thanh doi, thanh de, thanh do
su sach » so sach, vu sach
dao tuc » dao duc
dau tuc » dau tu, cau truc, dau nuoc
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet
lang xa » dang xay, lang van
lang ha » long ha
di cua » dai cua, doi cua, de cua

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 ty ((lang xa) OR (lang ha)) hoi. lieu va ((dau tuc) or (dao tuc)) van thanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((lang xa) OR (lang ha)) hoi. lieu va ((dau tuc) OR (dao tuc)) van thanh di cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((lang xa) OR (lang ha)) hoi. lieu va ((dau tuc) or (dao tuc)) van thanh di cua tre*".