Perhaps you should try some spelling variations:
ngang thanh » nang thanh, nganh thanh, ngan thanh
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
hanh trong » hanh trang, anh trong, hinh trong
trong nam » thong nam, trong lam, trong cac
dung cong » dung trong
thanh hai » thanh phan, thanh hoa, thanh san

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) OR (chieu sang)) - hanh trong nam ((dang cong) or (dung cong)) ngang thanh hai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sang) OR (chieu sang)) - hanh trong nam ((dang cong) OR (dung cong)) ngang thanh hai.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sang) OR (chieu sang)) - hanh trong nam ((dang cong) or (dung cong)) ngang thanh hai".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sang) OR (chieu sang)) - hanh trong nam ((dang cong) or (dung cong)) ngang thanh hai*.