findnodes returns a node list. You have to iterate over it the same way you already did for the parent node: 
for my $test ($xml->findnodes('/parent_node')) {
    for my $mystring ($test->findnodes('node2/child_node_a')) {
        print $mystring, "\n";
    }
}

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In reply to Re: Duplicate XML Node Question by choroba
in thread Duplicate XML Node Question by omegaweaponZ

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