If you want to entice a cat to come closer, don't look at it! Direct eye contact is seen as threatening.
Put out your hand, point your face away from the cat, and put your hand out while gently calling it over. Your success rate will be much higher!
Also, a good cat-noise to attract them is a light trill with an upward inflection. It's my go-to when assuring nervous/unsure cats.
