Perhaps you should try some spelling variations:
thieu sang » thieu khang, thieu quang, hieu lang
chieu sang » chieu sach, chieu xanh, hieu lang
hanh trang » thanh trung, canh tranh, hanh trinh
nhung cong » dung cong, thong cong, hang cong
trang va » tran van, hang va
cong dan » cong san, cong tan, huong dan

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