Perhaps you should try some spelling variations:
opto mechatronics » opto mechatronic, _ optomechatronics, opto mechanics
etc mechatronics » c mechatronics, data mechatronics, _ mechatronics
1 mechatronics » _ mechatronics, 1 mechanics, _ biomechatronics
2c robotics » 2 robotics, 21 robotics, 26 robotics
6 robotics » _ robotics, 6 robotic, a robotics
2 robotic » 12 robotic, _ robotic, a 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 (2 robotic))) OR (6 robotics))%((1 mechatronics) OR (((etc mechatronics) OR (opto mechatronics))))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%22control%((((2c robotics) or (2 robotic))) or (6 robotics))%((1 mechatronics) or (((etc mechatronics) OR (opto mechatronics))))%22".
• Adding a wildcard symbol may retrieve word variants: %22control%((((2c robotics) or (2 robotic))) or (6 robotics))%((1 mechatronics) or (((etc mechatronics) OR (opto mechatronics))))%22*.