@98025892 There's nothing much you can do except for the replacing the whole display. Oem, new are cheap (20-40$) so this shouldn't be a problem. This first screen layer is an antireflective, antistatic surface. Those "bubbles" are signs and effects of the chemical reaction already started between the display layers. That is also a normal thing, because of and due to the age of the device. Replacing the part is fairly easy and doesn't take long. At the end you can put on it some protective glass. 

 @f275d986 Thank you. I have seen that it's possible to replace the display cover, I'll try to find one cheap.