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
hanh mang » nhanh mang, hanh trang, nhanh lang
van toan » van tuan, van thanh, manh toan
mang va » mang vua, hang va, bang va
van tan » van tuan, van ban, van tai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ho ((hieu lang) OR (hieu quang)) - hanh mang va nhung cong ((van toan) or (van tan)) tap~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (hieu quang)) - hanh mang va nhung cong ((van toan) OR (van tan)) tap.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu lang) OR (hieu quang)) - hanh mang va nhung cong ((van toan) or (van tan)) tap".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu lang) OR (hieu quang)) - hanh mang va nhung cong ((van toan) or (van tan)) tap*.