It seems you want to search for terms from file2 in file1. I'm not sure why you are building the hash, but if you just want to search for all the elements of file2 in all the elements of file1, you can build a large regex from the second csv and use that to search the first one: 
#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };
use autodie;

use Text::CSV;


sub build_regex {
    my ($filename) = @_;
    my @regexes;
    my $csv = 'Text::CSV'->new;
    open my $fh, '<', $filename;
    while (my $row = $csv->getline($fh)) {
        push @regexes, join '|', map quotemeta, @$row;
    }
    return join '|', @regexes
}


sub find_matches {
    my ($filename, $regex) = @_;
    my $csv = 'Text::CSV'->new;
    open my $fh, '<', $filename;
    while (my $row = $csv->getline($fh)) {
        /$regex/ and say for @$row;
    }
}


my ($f1, $f2) = qw( 1.csv 2.csv );

find_matches($f1, build_regex($f2));

[download]
($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re^3: match a portion of a string from a file by choroba
in thread match a portion of a string from a file by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.