Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hieu sang » chieu sang, hieu lang, nhieu tang
cuong tap » luong tap, cong tac, luong tai
anh dung » anh dong, anh huong, sach dung
luan san » luan van, luan hoan, luan phan
cong tap » cong tac, cong tan, tong tap
toan tap » toan ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu sang) OR (hieu quang)) - anh dung luan san ((cong tap) or (cuong tap)) toan tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu sang) OR (hieu quang)) - anh dung luan san ((cong tap) OR (cuong tap)) toan tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc ((hieu sang) OR (hieu quang)) - anh dung luan san ((cong tap) or (cuong tap)) toan tap".
• Adding a wildcard symbol may retrieve word variants: doc ((hieu sang) OR (hieu quang)) - anh dung luan san ((cong tap) or (cuong tap)) toan tap*.