Simon,
I think some people post a 'BTT' or 'Marked' comment so they can locate that specific topic later by reviewing the postings they have already contributed to.
Simon said:
You can search the site on Google, just include "site:www.jehovahs-witness.net" when you do.
There are advanced options that allow you to search by date range etc... as well.
Since there have been complaints regarding the existing search function, is it possible to discontinue your search function but then have a search button which links directly to Google by default so that the 'site' limiter is already included?