Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
chieu sang » chieu sach, chieu xanh, nhieu tang
hieu lang » hieu quang, nhieu tang, hieu van
trinh qua » trinh quan, trinh cua, trinh quang
tong cong » trong cong, cong cong, dung cong
san toan » van toan, dan toan, manh toan
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: nho ((hieu lang) OR (chieu sang)) - hanh trinh qua ((thong thong) or (tong cong)) san toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nho ((hieu lang) OR (chieu sang)) - hanh trinh qua ((thong thong) OR (tong cong)) san toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nho ((hieu lang) OR (chieu sang)) - hanh trinh qua ((thong thong) or (tong cong)) san toan ban".
• Adding a wildcard symbol may retrieve word variants: nho ((hieu lang) OR (chieu sang)) - hanh trinh qua ((thong thong) or (tong cong)) san toan ban*.