Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
nhung cong » dung cong, hang cong, nhung don
thong cong » trong cong, tong cong, thong thong
hoc thieu » toc thieu, hoc hien
tong quan » thong quan, tong luan, luong quan
nang quan » ban quan, nang suat
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap

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 sang - hanh ((tong quan) or (nang quan)) ((nhung cong) OR (thong cong)) dan than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - hanh ((tong quan) OR (nang quan)) ((nhung cong) OR (thong cong)) dan than cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu sang - hanh ((tong quan) or (nang quan)) ((nhung cong) OR (thong cong)) dan than cao".
• Adding a wildcard symbol may retrieve word variants: hoc thieu sang - hanh ((tong quan) or (nang quan)) ((nhung cong) OR (thong cong)) dan than cao*.