Perhaps you should try some spelling variations:
dung cong » dung trong
cong lang » cong vang, cong luong, cong quang
lang gian » dan gian, nang giao, lang bien
doc hieu » hoc thieu, hoc hien
dong pha » dong phan, dong ha, dong nha
pha dung » pham dung, phan dung, kha dung
gian dan » gian lang

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) OR (toc thieu)) nganh - van dong pha dung cong lang gian dan~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doc hieu) OR (toc thieu)) nganh - van dong pha dung cong lang gian dan".
• Adding a wildcard symbol may retrieve word variants: ((doc hieu) OR (toc thieu)) nganh - van dong pha dung cong lang gian dan*.