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, 1 robotics, 11 robotics
2 robotics » _ robotics, a robotics, 6 robotics
26 robotic » 6 robotic, 22 robotic, 16 robotic
2 robotic » 12 robotic, _ robotic, 3 robotic

Try widening your search to All Fields.

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 (((2 robotics) OR (2 robotic))))) OR (26 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 (((2 robotics) or (2 robotic))))) or (26 robotic))%((2c mechatronics) OR (c mechatronics))%22".
• Adding a wildcard symbol may retrieve word variants: %22control%((((((2c robotics) or (21 robotics))) or (((2 robotics) or (2 robotic))))) or (26 robotic))%((2c mechatronics) OR (c mechatronics))%22*.