Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
nhung cong » dung cong, thong cong, hang cong
hieu lang » chieu sang, nhieu tang, hieu van
thong qua » thong quan, thong cua, thong tu
cong van » cong vang, cong san, song van
van toan » van tuan, van tan, van thanh
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: theo ((hieu lang) OR (hieu quang)) - thanh ((thong xay) or (thong qua)) nhung cong van toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu lang) OR (hieu quang)) - thanh ((thong xay) OR (thong qua)) nhung cong van toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu lang) OR (hieu quang)) - thanh ((thong xay) or (thong qua)) nhung cong van toan cao".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu lang) OR (hieu quang)) - thanh ((thong xay) or (thong qua)) nhung cong van toan cao*.