Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, diep quang
dung cong » dung trong
chinh va » chinh ta, chinh tai, hanh va
cong van » cong vang, cong san, song van
van toan » van tuan, van tan, van thanh
toan cau » toan cao, toan ban, toan tap
va dung » van dung, va duong, vat dung

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu quang) or (hieu qua)) - hanh chinh va dung cong van toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu quang) OR (hieu qua)) - hanh chinh va dung cong van toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu quang) or (hieu qua)) - hanh chinh va dung cong van toan cau*.