Others have provided examples using grep. Here is a non-grep example. 
#!/usr/bin/env perl
use warnings;
use strict;

my @test2 = (
    ["KATE"     , "1001"],
    ["XERXES"   , "1002"],
    ["LARRY"    , "1003"],
    ["TEDDY"    , "1004"],
    ["DANA"     , "1005"],
    ["SHERRY"   , "1006"]
);

my @grepnames;
for my $aref (@test2) {
    push @grepnames, @$aref[0] if (@$aref[0] =~ /ER/);
}
print "@grepnames\n";

[download]

prints: 

XERXES SHERRY

[download]
A good resource for this type of task is perldsc.

In reply to Re: substring search in an array of arrays by toolic
in thread substring search in an array of arrays by jgatrell42

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