Perhaps you should try some spelling variations:
thieu quang » hieu quang, thien quan, trien quang
cong ngang » cong nhan, cong quang, cong nong
hoc thieu » toc thieu, hoc hien
cong lang » cong vang, cong luong, cong quang
toan ban » van ban
va hang » van hang, va nang, va hanh
va lang » va nang, hoa lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu quang - canh tranh ((va hang) or (va lang)) ((cong ngang) OR (cong lang)) toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu quang - canh tranh ((va hang) OR (va lang)) ((cong ngang) OR (cong lang)) toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu quang - canh tranh ((va hang) or (va lang)) ((cong ngang) OR (cong lang)) toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc thieu quang - canh tranh ((va hang) or (va lang)) ((cong ngang) OR (cong lang)) toan ban*.