how can I find all the files in different folds which contains a word?
 

what can I do?

What about google ?

This time I did it for you... (check this)

midnight commander AKA "mc" will also do it for you
command > find file
mc is a CLI program so you have to run it from a some kind of terminal

I am just using PERL File::Util to get out all files and directories .

grep -R

grep -rl "text-to-search-for" /path/to/files

#!/usr/bin/perl
use feature ':5.10';
use warnings;
use strict;

use File::Util;

my($f) = File::Util->new();
my(@dirs_and_files) = $f->list_dir('/home/mei/Downloads/core.samples.v0.1b6/effo','--recurse');

foreach(@dirs_and_files) {
my($myfile) = $_;
open(my $fh, '<', $myfile) or continue;
while(<$fh>){
chomp;
if($_ =~ m/__GNUC__/){
say $myfile;
last;
}
}
}

a simple solution.