RT-4.0.5 : Can't do Simple Search on Articles

In RT-3.8.8 we could do simple search on the RTFM articles, but, in RT-4.0.5 we cannot.

Also I noticed the test RT-4.0.5 instance on Best Practical's website that RTFM is included in the "Home" Pulldown but ours is not.

Maybe there's a simple config change we can make to the RT_SiteConfig.pm file ?

Thanks in advance,
Scott