It's that classic blunder, less well known than getting involved in a land war in Asia: use of numbered variables instead of an array! Especially when the OP calls for it.

use strict;
use warnings;

my @aoh;
push @aoh, { one => 1, two => 2 };
push @aoh, { three => 3, four => 4 };
push @aoh, { five => 5, six => 6 };

dump_keys( $_ ) for @aoh;

sub dump_keys { print "$_\n" for keys %{+shift} }
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Update: jeffa has since revised his answer to make my comment irrelevant.