Most greps have an option to give a filename containing a list of strings to search for, so use that. Since you're using words rather than patterns, use the fixed strings option as well:

find blah blah blah | xargs grep -i --fixed-strings --file=words.dat
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...roboticus

When your only tool is a hammer, all problems look like your thumb.

find blah blah blah | xargs grep -i --fixed-strings --file=words.dat

Change that to ...

find blah blah blah -print0 | xargs -0 grep -i --fixed-strings --file=
+words.dat
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... and problems with "funny" filenames are gone.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

What have you tried?

Perl's search operator can do or operations.

   while(<INFILE>) {
       if(/(sales|price|invoice)=/) {
            # do stuff
       }
   }
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Something like this?

#!/usr/bin/perl

use strict;
use warnings;

use File::Find;

my $re = get_re();
my @dirs = qw/./;

find(\&wanted, @dirs);


sub wanted {
    return unless -f $_;

    open my $fh, "<", $_ or warn "Couldn't open $_: $!\n";

    while (<$fh>) {
        print "$File::Find::name:$_" if /$re/;
    }
}

sub get_re {
    my @words;

    while(<DATA>) {
        chomp;
        push @words, $_;
    }
    return join '|', map { "$_=" } @words;
}


__DATA__
sales
price
invoice
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