How to hide options in the second select before choosing option in first select
If I am not mistaken, you want to show in the second filter only the towns (villages) related to the selected city (ville) in the first filter. That means, the content of the second filter depends on the selection in the first filter. Am I right?

In that case, you might try something like the Views Dependent Filters module. See below its description:


  Suppose you had a view showing several kinds of products, such as
  cake, bicycles, and books, and an exposed filter on product type that
  lets the user refine the listing to one or more types.
  
  With this module you could add the following filters:

cake flavour, such as lemon, chocolate, coffee
bicycle size
book genre

  
  Each filter will only show when the type it relates to is selected in
  the filter for product type.