Perhaps you should try some spelling variations:
nhung cong » thong cong, hang cong, nhung don
thieu sang » chieu sang, thieu khang, thieu quang
hoc thieu » toc thieu, hoc hien
lanh ban » lanh bang, lang ban, doanh ban
dan chan » dan gian, dan ca, van chat
ban cua » ban quan
chan tu » phan tu, han tu, chon tu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - lanh ban cua ((nhung cong) OR (((dung cong) OR (dung trong)))) dan chan tu~.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - lanh ban cua ((nhung cong) or (((dung cong) or (dung trong)))) dan chan tu*.