You don't need assertions to match a string next to a string

#!/usr/bin/perl --
use strict; use warnings; use Data::Dump qw/ dd /;
my $data = q{
This is CentOs 6.5 version and CentOs  5.5 is not supported.
The CentOS 6.0 has ability for LVM Snap backups where as CentOs 5.5 do
+esn't.};
my @centos = $data =~ /CentOs\s+(\S+)/g;
dd( \@centos );
__END__
[6.5, 5.5, 5.5]
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