Perhaps you should try some spelling variations:
chieu tinh » trieu tinh, lieu tinh, chau tinh
hieu quang » thieu quang, hieu quan, hieu qua
nhung cong » dung cong, thong cong, hang cong
trang va » hang va
tran van » luan van
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((chieu tinh) or (hieu quang)) - hanh ((trang va) or (tran van)) nhung cong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((chieu tinh) OR (hieu quang)) - hanh ((trang va) OR (tran van)) nhung cong dan toan cao.
• Adding a wildcard symbol may retrieve word variants: ho ((chieu tinh) or (hieu quang)) - hanh ((trang va) or (tran van)) nhung cong dan toan cao*.