"나 이거는 좀 아닌 거 같다 하는 부분이 있다면?" may be translated in many ways.
=> If any part of it makes you think "um, this can't pass [be]" ...
=> If there is anything in it that gives you (a feeling of) reservation ...
=> If any part of it raises a doubt in you ...
=> If anything in it makes you scratch your heard ...