Perhaps you should try some spelling variations:
doi chieu » doc hieu, doi chi, mot chieu
sang cong » dang cong, bang cong, hang cong
cong khan » cong khanh, cong nhan, cong phan
khan than » phan than, khoan thanh, khanh thanh
han dung » chan dung, han duong, hanh dung
dung lua » dung luan, dung luat, dung cua
lua sang » luc sang, bua sang, cua sang
than tu » thanh tu, thang tu, phan tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) or (toc thieu)) sang - han dung lua sang cong khan than tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (toc thieu)) sang - han dung lua sang cong khan than tu.
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) or (toc thieu)) sang - han dung lua sang cong khan than tu*.