Perhaps you should try some spelling variations:
thieu sang » chieu sang, thieu khang, thieu quang
hoc thieu » toc thieu, hoc hien
tong cong » trong cong, cong cong, dung cong
nhan dan » phan dau, gian dan
cong dan » cong san, cong tan, huong dan
dan nhan » danh nhan, dan chan, van nhan
nhan tai » hang tai, van tai, toan tai
nhan va » nhan tao, phan van
han va » hang va, hanh va, ban va

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