How search inside an entry. Not "find all items" but search within the item

Here is what I am trying to do:
1. First level search is the normal search to find items with a string.
2. The item in question is a listing of IP addresses and host names over 6000 characters long, with many similar sets of data.
3. Here is an excerpt:

[VPN - from LAN]
10.1.1.100 http://www.rephunter.net
10.1.1.100 test.rephunter.net
10.1.1.103 qa.rephunter.net
10.0.0.115 dev.rephunter.net
10.1.1.101 mysql.rephunter.net
10.0.0.125 dev-mysql.rephunter.net
10.1.1.126 mail.rephunter.net
10.0.0.121 svn.rephunter.net

===

[LAN]

[removed from dev httpd-vhosts.conf 2013-02-27]
184.97.189.199 Qwest

[comcast DNS nameservers]
24.94.163.100 (obsolete)
24.94.163.101
as of 18-May-09 changed to
68.87.77.130
68.87.72.130
68.87.75.194
as of 05-May-10, per http://dns.comcast.net/dns-ip-addresses.php
68.87.77.134
68.87.72.134

Since this document is quite long, finding something in it manually by scanning the list is quite tedious and error prone. I would expect there to be an ability to search it. Right now the workaround is to copy the content to another editor and search.

This feature would be similar to having an email client that would allow searching to find emails containing a string, but not allow searching the content of an email to find the string in context.

Understand?