what kind of oil makes your eyelash grow?

Snake oil..... google it

There is nothing you can do to make them longer.

You can get medications from your doctor to help them not fall out.

Castor oil. Works for eyelashes too. I use it and it's great. Some people have had bad experiences with it so be careful, discontinue use if the hairs start to fall out. There's also something called Latisse or something like that, a lot of people say it works.