Perhaps you should try some spelling variations:
chieu sang » chieu sach, chieu xanh, nhieu tang
nhung cong » dung cong, thong cong, hang cong
hieu lang » hieu quang, nhieu tang, hieu van
trung ha » trung hoc, trung cap
cong tap » cuong tap, cong tac, cong tan
tap toan » tap doan, tap quan, bai 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: nho ((hieu lang) OR (chieu sang)) - thanh ((trung ha) or (trung tam)) nhung cong tap toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nho ((hieu lang) OR (chieu sang)) - thanh ((trung ha) OR (trung tam)) nhung cong tap toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nho ((hieu lang) OR (chieu sang)) - thanh ((trung ha) or (trung tam)) nhung cong tap toan cao".
• Adding a wildcard symbol may retrieve word variants: nho ((hieu lang) OR (chieu sang)) - thanh ((trung ha) or (trung tam)) nhung cong tap toan cao*.