use strict;
use warnings;

my @doc_nums = qw(1 2 3 4 5 6 7 8 9);
my @docs;
    my @doc;

foreach( @doc_nums ) {
    @doc = ();
    push @doc, int rand 10 for 1..3;
    push @docs, [@doc];
}

print "@$_\n" for @docs;