tunnel vision
noun /ˌtʌnl ˈvɪʒn/
/ˌtʌnl ˈvɪʒn/
[uncountable]- (medical) a condition in which somebody can only see things that are straight ahead of them
- (disapproving) a lack of ability to see or understand all the aspects of a situation, an argument, etc. instead of just one part of it