The sound made when scraping the eye is caused by the expulsion of air from the conjunctival sac. Since there is a potential cavity between the inner side of the eyelid and the eye, called the conjunctival sac, there is lubricating fluid secreted by the lacrimal gland between the cavities to play a lubricating role. Therefore, when scraping, due to the force of the finger drive caused by the eyelid folds, can lead to air into the conjunctival sac, and then the air is squeezed out of the body, can lead to the sound when pressing again, this is a normal phenomenon, do not worry too much.