"Test"->{qwe} = 111;
"Test"->[1] = 222;
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Examples from perlref dealing with symbolic references:

  $name = "foo";
  $$name = 1;                 # Sets $foo
  ${$name} = 2;               # Sets $foo
  ${$name x 2} = 3;           # Sets $foofoo
  $name->[0] = 4;             # Sets $foo[0]
  @$name = ();                # Clears @foo
  &$name();                   # Calls &foo() (as in Perl 4)
  $pack = "THAT";
  ${"${pack}::$name"} = 5;    # Sets $THAT::foo without eval
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Abigail

I've already realized what this is just symbolic reference

No, it isn't. A symbolic ref uses the string in the variable as the name of a package variable:

my $f = "foo";
our $foo = "blah";
print $$f;

__OUTPUT__
blah
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The behavior you're seeing in your example code is autovivification. You tell Perl that you want a hashref, so you get one. This behavior is forbidden by use strict 'refs'. For that, you should explicitly put a hashref into the variable, such as with my $var = { }; or  my $var = \%hash;.

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Note: All code is untested, unless otherwise stated