...so it would find any combination of the two words

You could also do it without grep and temp files:

#!/usr/bin/perl

my @words = qw(we love);

while (<DATA>) {

    # all search words must appear, but order is irrelevant
    my $found = 0;
    for my $search (@words) {
        $found = /\Q$search/i;
        last unless $found;
    }
    print if $found;
}

__DATA__
foo we love bar
love we foo bar
foo love bar we
foo we bar
love foo bar
[download]

Output:

foo we love bar
love we foo bar
foo love bar we
[download]

In place of the special DATA handle I'm using here for demo purposes, you'd use the file handle you've opened to your input file, i.e.

open my $fh, "<", $DataIn or die "Couldn't open '$DataIn': $!";

while (<$fh>) {
    ...
[download]

Interestingly enough, the file is never opened. There are 4 grep calls before my altered one. Any reason that the grep line is enclosed in ``? here are the previous calls.

if($aquiSW =~ /New Stuff/i)
 {`grep -i \"1\$\" $DataIn > $DataTmp`;
 $DataIn=$DataTmp;
 if($DataTmp eq $DataTmpa){$DataTmp=$DataTmpb;} # if
 else{$DataTmp=$DataTmpa;} # else
} # if aquiSw
if($lA && $Artist ne ".*")
 {`grep -i \"\^$Artist\" $DataIn > $DataTmp`;
 $DataIn=$DataTmp;
 if($DataTmp eq $DataTmpa){$DataTmp=$DataTmpb;} # if
 else{$DataTmp=$DataTmpa;} # else
} # if $IA
if($lL && $Label ne "*"){`grep -i \"\|$Label\" $DataIn > $DataTmp`;
 $DataIn=$DataTmp;
 if($DataTmp eq $DataTmpa){$DataTmp=$DataTmpb;} # if
 else{$DataTmp=$DataTmpa;} # else
} # if $IL
if($lN && $LabelNo ne "*"){`grep -i \"\|$LabelNo\" $DataIn > $DataTmp`
+;
 $DataIn=$DataTmp;
 if($DataTmp eq $DataTmpa){$DataTmp=$DataTmpb;} # if
 else{$DataTmp=$DataTmpa;} # else
} # if $IN
[download]

Interestingly enough, the file is never opened.

The reason is that the external program 'grep' is opening the file itself.

Any reason that the grep line is enclosed in ``?

Backticks (``) run an external program, like the grep here.

My suggestion was to not use backticks at all, as Perl is perfectly capable of doing grep-like jobs all by itself...  and probably a lot faster, too, than when calling the external grep multiple times.  Of course, you'd have to restructure the program accordingly...

AFAICT, the consecutive runs of grep (in combination with the use of the temp files) achieve to extract lines where all the tested conditions match.  A restructured solution without using grep could look something like this:

...
LINE: while (<$fh>) {

    if ($aquiSW =~ /New Stuff/i) {
        next LINE unless /1$/;
    }

    if ($lA && $Artist ne ".*") {
        next LINE unless /^\Q$Artist/i;
    }

    if ($lL && $Label ne "*") {
        next LINE unless /\|\Q$Label/i;
    }

    # ...

    if ($lT && $Title ne "*") {
        # split $Title into @words...
  
        for my $word (@words) {
            next LINE unless /\Q$word/i;
        }
    }

    # ...
        
    # we only get here if all the tested conditions matched
    print;
}
[download]

I would say the problem lies in the "switching" of files. On the next iteration of the loop, result of the previous grep is used as input. Therefore, in your example, the word "LOVE" is being searched only on lines already containing "WE".

You should grep always the original input file. But it would be faster to search for all the words at the same time, i.e. changing "WE LOVE" to "WE\|LOVE" (by something like $wrd =~ s/ /\\|/g) and greping just for this.

Thanks for the reply. Problem is that there are 5 diff greps, and each does the same thing, switching the files, so each iterance of the file is already "slimmed" down. This is for phonograph records, so there may have been an artist or label already GREPed. This has always worked fine, only my alteration does not. And the reason I use an array is there could be one word, 2,3,4 etc.

I would switch to ack