Perhaps you should try some spelling variations:
advanced countries » advanced control, advanced course, advanced queries
advanced courses » advanced course, advanced cases, advanced classes
city barcelona » life barcelona, view barcelona, wism barcelona
die barcelona » de barcelona, life barcelona, _ barcelona

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((advanced courses) OR (advanced countries)) in mathematics - ((city barcelona) OR (die barcelona)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((advanced courses) OR (advanced countries)) in mathematics - ((city barcelona) or (die barcelona))".
• Adding a wildcard symbol may retrieve word variants: ((advanced courses) OR (advanced countries)) in mathematics - ((city barcelona) or (die barcelona))*.