Here is solution, for there could be more then one value for key that matches $str in a HoH.

# The could be more then one value for key,
# when you search for key $st, in a HoH.

my $st = 'alamo';

my @values = map  {$_->{$st}}
             grep {$_->{$st}}
             @{$h}{keys %$hash};
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