Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tinh dai » trinh dai, tinh da, tinh hai
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va
hoc may » hoc ma
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang
am hoc » ad hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach y lang xa hoi. ((hieu ve) OR (hieu van)) am hoc may tinh dai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y lang xa hoi. ((hieu ve) OR (hieu van)) am hoc may tinh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y lang xa hoi. ((hieu ve) OR (hieu van)) am hoc may tinh dai cua tre*.