Not completely true, It depends on the situation: when a boy is talking to her and the way he keeps his eye contact and smile with her as well is sometimes making the girl feel intimidated.
If you are talking to her for the first time, sometimes it makes them paralyze or numb.
Her fist automatically gets closed and she frequently blinks her eyes and it gradually increases unless until the boy maintains perfect way of eye contact with her with a gentle smile on his face.
Make a Friendly Environment:
Be funny
Be kind and gentle
JUST A BRO TIP:
Tilt your head to 20 degrees: either going to your left or right with a gentle smile on your lips and tantalizing eyes while having the conversation with short girls.
It looks so sweet and romantic for them!