Perhaps you should try some spelling variations:
2c mechatronics » etc mechatronics, _ mechatronics, 1 mechatronics
c mechatronics » _ mechatronics, 1 mechatronics, a mechatronics
2c robotics » 26 robotics, 29 robotics, c robotics
21 robotics » 2.1 robotics, 11 robotics, 21 robotic
1 robotics » _ robotics, 6 robotics, 1 robotic
2 robotics » _ robotics, 6 robotics, 5 robotics
26 robotic » 6 robotic, 22 robotic, 16 robotic
2 robotic » 12 robotic, _ robotic, 3 robotic

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: %22control%((((((2c robotics) OR (((21 robotics) OR (1 robotics))))) OR (2 robotics))) OR (((((26 robotic) OR (2 robotic))s) OR (((26 robotic) OR (2 robotic))))))%((2c mechatronics) OR (c mechatronics))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22control%((((((2c robotics) or (((21 robotics) OR (1 robotics))))) or (2 robotics))) or (((((26 robotic) or (2 robotic))s) or (((26 robotic) or (2 robotic))))))%((2c mechatronics) or (c mechatronics))%22".
• Adding a wildcard symbol may retrieve word variants: %22control%((((((2c robotics) or (((21 robotics) OR (1 robotics))))) or (2 robotics))) or (((((26 robotic) or (2 robotic))s) or (((26 robotic) or (2 robotic))))))%((2c mechatronics) or (c mechatronics))%22*.