Perhaps you should try some spelling variations:
hieu quang » thieu quang, hieu quan, hieu qua
hieu lang » chieu sang, nhieu tang, hieu van
canh sinh » canh tinh, canh binh, tinh sinh
vat nhung » va nhung, vap nhung, vai nhung
cong dan » cong san, huong dan, cong dong
cong tan » cong tac, cong san, cong thanh
chan cau » phan cau, can cau, chinh cau

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)) - canh sinh vat nhung ((cong dan) or (cong tan)) chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ho ((hieu lang) OR (hieu quang)) - canh sinh vat nhung ((cong dan) OR (cong tan)) chan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "ho ((hieu lang) OR (hieu quang)) - canh sinh vat nhung ((cong dan) or (cong tan)) chan cau".
• Adding a wildcard symbol may retrieve word variants: ho ((hieu lang) OR (hieu quang)) - canh sinh vat nhung ((cong dan) or (cong tan)) chan cau*.