Perhaps you should try some spelling variations:
thieu khang » chieu khong, thieu quang
thieu sang » chieu sang, thieu quang, hieu lang
nhung cong » dung cong, thong cong, hang cong
cua nhung » va nhung
lanh ban » lanh bang, lang ban, doanh ban
cong dan » cong san, cong tan, huong dan
than cao » thai cao, than cap, than sao
toan cao » toan ban, toan tap
ban cua » ban quan

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) OR (thieu khang)) - lanh ban cua nhung cong dan ((than cao) OR (toan cao))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (thieu khang)) - lanh ban cua nhung cong dan ((than cao) or (toan cao))~".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (thieu khang)) - lanh ban cua nhung cong dan ((than cao) or (toan cao))*.