I can't reproduce your problem. Your code will print $line many times if more than one element of @all appears in $line. The following code eliminates the loop and replaces it with a single regular expression - maybe you can work from this example or show us data where this example doesn't do what you mean it should:

#!perl -wl
use strict;

my @all = qw( rsriram Corion );

my $re = sprintf '\b(?:%s)\b', join "|", map { quotemeta } @all;
$re = qr/$re/;
print "Searching for $re\n";

for (<DATA>) {
    chomp;
    if (/$re/) {
        print "Found at least one match in '$_'\n";
    } else {
        print "Ignoring '$_'\n";
    };
};

__DATA__
This is a line that mentions rsriram.
This is a line that mentions Corion.
This is a line that mentions Corion and rsriram together.
This is a line that mentions neither of the two.
This line intentionally left blank.
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