in reply to How to remove other language character from a string

You need to use utf8; to tell Perl that your source file is in UTF-8. That way non-ASCII literal strings work the way you want them to.

use strict;
use warnings;
use 5.010;
use utf8;
binmode STDOUT, ':encoding(UTF-8)';

my $str = "ครัวซองเเซนด์วิชไข่ดาว Croissant Egg Sandwich ครัวซองเเซนด์วิชไข่ดาว";
$str =~ s/[^\p{Latin}\p{Common}]//g;
$str =~ s/^\s+|\s+$//g;
say $str;
Croissant Egg Sandwich

See also: Character Encodings in Perl.

Updated to unlinkify the brackets, and to exclude \p{Common} instead of \s from removal.