Hi Jim,
Per Rogers comments above - when I checked your account there were no keywords entered for the Show (Channel) Level and Episode (Item) Level keywords.
To enter in the Keywords for the show level - when you log into your libsyn account - click on the gears icon next to your artwork in the upper left. Then enter your keywords / tags and click save.
For Keywords for your episodes - you will need to go click Edit for each episode in the episode list and one episode at a time add in the keywords.
If you put yourself into the "Advanced" editing mode - and then go to "Description" you will see the place for editing the keywords near the lower right. Click on "Tags / Keyword" and enter you keywords in the box below and then click on Publish when you are done.
Please note it may take up to a week for the changes to be reflected in search results in iTunes. And even then search results are sorted based on the all time number of subscribers your show has in iTunes.
So to better place yourself in the search results you need to increase the number of subscribers you have via iTunes.
Good Luck,
Rob Walch
Libsyn