use strict;
use warnings;

my @bah = ( "Australia", "Austria", "Finland", "Norway" );
my $regex = join ('|', map { "(?:$_)" } @bah);

my $foo = "In Australia the people from Austria drink beer at the pub with the people from Norway";

my $result = "";
my @data = $foo =~ /($regex)/g;

print join ", ", @data;