Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hanh tranh » canh tranh, hanh trinh, hanh trang
hieu lang » chieu sang, nhieu tang, hieu van
tranh cua » doanh cua, manh cua
tong tap » tuong tac, trong tan, cong tac
cong tan » cong tac, cong san, cong 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)) - hanh tranh cua cong ((tong tap) or (cong tan)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo ((hieu lang) OR (hieu quang)) - hanh tranh cua cong ((tong tap) OR (cong tan)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo ((hieu lang) OR (hieu quang)) - hanh tranh cua cong ((tong tap) or (cong tan)) toan cao".
• Adding a wildcard symbol may retrieve word variants: theo ((hieu lang) OR (hieu quang)) - hanh tranh cua cong ((tong tap) or (cong tan)) toan cao*.