Products not showing on home and categories pages

[ByMed]

This is the website (not created by me, fortunately): www.svapoline.it

 

It does not show products on the home page and in some categories pages.

I noticed that if a category contains 1/3/not a lot of products (like Additivi or Basi neutre), they are listed, but, when it comes to "Ecig" or "Liquidi" with their 100+ products, nothing is displayed.

 

So strange...

 

I set "50 products per page" and every block (modules: new products, special offers, et cetera) to show 50 products (even if they are one year old, but not more, just 365 days ago at most). I checked that every category is accessible from visitors and registered customers.

 

Although that, it does not work.

 

WHY?

 

Please help me...

 

Sorry for my English (please correct my mistakes).