IDIOMS 16

have eyes in the back of your head to know what is happening all around you, even when this might seem impossible:
• You need to have eyes in the back of your head to be a teacher.


on the ball INFORMAL thinking or acting quickly and intelligently:
• A photographer who was on the ball got some great pictures of the incident.


catch sb's eye
a) to attract someone's attention and make them look at something:
• All of a sudden, something red caught Barb's eye.b) to look at someone at the same moment that they are looking at you:
• I caught Ben's eye in the rear-view mirror and knew what he was thinking.


have a (good) eye for sth to be good at noticing and recognizing what is attractive, valuable, of good quality etc.:
• Greene has an eye for detail.


not see the forest(wood) for the trees to be unable to understand something because you are looking too much at small details rather than the whole thing