It's probably not the best way to do it but this is what sprang to mind when I saw this post. It's also very similar to what you already have.

use strict;

my @keywords = qw/foo bar 12345 abcd/;
my $string = "foobarfoo1234523423412345abcdefsadfabc";

my $re = join('|',@keywords);

my %result;
$result{$1}++ while ($string =~ /($re)/ig);

foreach my $s (keys %result){
  print "$s=>$result{$s}\n";
}

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In reply to Re: Count multiple pattern matches by Mr. Muskrat
in thread Count multiple pattern matches by johnnywang

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