I did a bit of updating on the Search box where it searches the forum posts. Try it out and see if it works better for you now.
http://www.countryplans.com/search.html - use the lower Google search box.
I found this old chestnut with a search on "energy truss" - http://countryplans.com/smf/index.php?topic=4872.0
Also, the new updated forum software seems to be doing a better job on searches as well. Try that one in the upper right corner of any forum page.