I'm not sure I understand exactly what you are looking for, but here's my best guess. This splits the text you provided on the word "command", retains the pattern in the results, and spans newlines. If you're looking for something else (e.g., splitting only lines containing "command"), please be more specific and we can go from there.

use strict;
use warnings;

use Data::Dumper;

my $string = 
"command = adb
asd
  2t525
 command=adfaf
  adsgadg
asd";

my @results = split( /(?=command)/, $string );

print Dumper( \@results );
[download]

The @results array contains two elements:

$VAR1 = [
          'command = adb
asd
  2t525
 ',
          'command=adfaf
  adsgadg
asd'
        ];
[download]

HTH