Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
chieu sang » chieu sach, chieu xanh, nhieu tang
nhung cong » thong cong, hang cong, nhung don
hieu lang » hieu quang, nhieu tang, hieu van
trinh vat » trinh van, trinh luat, sinh vat
dung cong » dung trong
dan chan » dan gian, dan ca, van chat
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: doi ((chieu sang) or (hieu lang)) - hanh trinh vat ((nhung cong) OR (dung cong)) dan chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu sang) OR (hieu lang)) - hanh trinh vat ((nhung cong) OR (dung cong)) dan chan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu sang) or (hieu lang)) - hanh trinh vat ((nhung cong) OR (dung cong)) dan chan cau".
• Adding a wildcard symbol may retrieve word variants: doi ((chieu sang) or (hieu lang)) - hanh trinh vat ((nhung cong) OR (dung cong)) dan chan cau*.