Perhaps you should try some spelling variations:
thuong duong » tuong duong, thuong luong, chuong duong
hien quang » dien quang, bien quang, hieu quang
hanh trinh » hanh chinh
hien quan » thien quan, lien quan, vien quan
duong dan » duong dang, huong dan, duong van
dan toan » van toan, dan than, 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: hoc ((hien quang) OR (hien quan)) - ((hanh trinh) or (canh tranh)) va thuong duong dan toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien quang) OR (hien quan)) - ((hanh trinh) OR (canh tranh)) va thuong duong dan toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien quang) OR (hien quan)) - ((hanh trinh) or (canh tranh)) va thuong duong dan toan ban".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien quang) OR (hien quan)) - ((hanh trinh) or (canh tranh)) va thuong duong dan toan ban*.