Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tinh dai » trinh dai, tinh doi, sinh dai
tinh hai » tinh thai, tinh chat, trinh han
tu sach » thu sach, su sach, te sach
lang xa » lang ha, dang xay, lang van
tinh da » tinh va, tinh gia, tinh lao
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang
van am » van nam, van lam, van dam
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 van am hoc va ((((tinh dai) OR (tinh da))) or (tinh hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y lang xa hoi. hieu van am hoc va ((((tinh dai) OR (tinh da))) OR (tinh hai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach y lang xa hoi. hieu van am hoc va ((((tinh dai) OR (tinh da))) or (tinh hai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach y lang xa hoi. hieu van am hoc va ((((tinh dai) OR (tinh da))) or (tinh hai)) cua tre*.