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

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