bro i think it means for every value of x there exists at least one y. The value of y depends on what we choose x. suppose x = {1,2,3,4} It means for every value of x i.e if we take x =1 it should divide one number (as it divide 1) and if we take x =2 it should also divide one number and so on. So every value of x, it should divide some number and it is not necessary that some number should be the same for different x.
like everyone like someone it means that someone should not be the same for everyone.
this is the way i am thinking, Please correct me if i am wrong.