Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
sach ty » sach tu, sach thu, xach tay
van hac » van hoc, van ha, van hai
hac duy » pham duy, phan duy
duy van » duy vat, dung van
minh di » minh ai, minh de, minh duc
cua tre » cuu tre, cua triet, dua tren
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: thu ((sach ty) or (sach y)) nang x ho. hieu van hac duy van minh di ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((sach ty) OR (sach y)) nang x ho. hieu van hac duy van minh di ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((sach ty) or (sach y)) nang x ho. hieu van hac duy van minh di ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: thu ((sach ty) or (sach y)) nang x ho. hieu van hac duy van minh di ((cua tre) OR (cua te))*.