I tried following your suggestions and working on the code, but I am not capable of make it work.
What I'd like to do is count every occurrence of the given relation (con/con/E is a relation) with every couple of work I have. If in my file I have 3 occurrences of the string
computer/computer/S  .* con/con/E   .* processore/processore/S
I'd like for my output to be like this:
computer-processore)-->3
The new code I wrote is this one (I tried to make it more readable, and, by the way, I also fixed the fact that my input file had some line with just * and some other with .*) :

#!/usr/bin/perl
use strict;
use warnings;
open my $listaParole,"File_Input/Coppie_Parole.txt" or die;
 
my %hash;
while (my $line=<$listaParole>) {
  chomp $line;
  my ($word1, $word2) = split /:/, $line;
  $hash{$word1} = $word2;
}
close $listaParole;

open my $testo, "<Wiki_Pulito/Prova/Pattern2.txt" or die;  
open my $conteggio, ">Wiki_Pulito/Prova/Conteggio1.txt" or die;

my $count=0;
my %arrayris;

    while (my $text=<$testo>){
       for my $key (keys %hash){
     my $value = $hash{$key};
     if ($text =~/($key\/$key\/S)\s{0,4}(\.\*)\s{0,4}(con\/con\/E)\s{0
+,4}(\.\*)\s{0,4}($value\/$value\/S)\b/g){
                        $count++;
                }  

     my $arrkey=$key."-".$value;
     $arrayris{$arrkey}=$count;
           }
     }

while ( my ($k,$v) = each %arrayris ) {
    print $conteggio "($k) => $v\n";
  
}
close $testo;
close $conteggio;
[download]

Problem is, when I get the output, is a nice list and all, but it's not possible that every couple and relation has exactly the same number of occurrences. And that is exactly what I get, like this:

([aA]mplificator[ei]-[Tt]ransistor) => 27
([cC]ervello-[Tt]alamo) => 27
([Ee]ucariot[ia]-[Mm]embran[ae]) => 27
([Cc]erio-[Ii]sotop[oi]) => 27
([Cc]ellul[ae]-[Nn]ucle[oi]) => 27
([Tt]ronco-[Tt]orace) => 27
([Bb]raccio-[Aa]vambraccio) => 27
[download]

It says 27 even for couple that never appear in the same string with the given relation.
Thanks everyone for the help! Every suggestion is very well appreciated!