use 5.014;
use warnings;

my @hashes = (
    { bla => 'cat', blubb => 'dog' },
    { only => 'cat' },
    { just => 'dog' },
);

sub hr_contains_cat_and_dog {
    my $hr = shift;
    my ($has_cat, $has_dog);
    for (values %$hr) {
        $has_cat = 1 if /cat/i;
        $has_dog = 1 if /dog/i;
    }
    return $has_cat && $has_dog;
}

my @result = grep hr_contains_cat_and_dog($_), @hashes;

use Data::Dumper;
print Dumper \@result;
__END__
$VAR1 = [
          {
            'bla' => 'cat',
            'blubb' => 'dog'
          }
        ];