Not 100% sure which way you are trying to go.

If you want multiple keys to one hash value take a look at the CPAN module Tie::Aliashash. It lets you do

$hash{ 'foo', 'bar' } = 'baz';
[download]

If you want multiple values per key take a look at the CPAN module Tie::Hash::Multivalue. It lets you do

$hash->{'sample'} = 'one';
$hash->{'sample'} = 'two';
# $hash->{'sample'} now contains ['one','two']
[download]

among other things.