Revolving/Rotating/Evolving content is alwys an issue.
The immediate thing to look at is whether you can make the actual
content pages more prominent.
Ensure they have topical <title>s.
You could also ensure that the content pages use an H1 for hte Page
title.
Possibly wrap an intro line or hang line immediately after with an H2
tag.
Check the Homepage and see what tags/elemetns are being used for the
entries being displayed.
you might beable to wrap the titles/links in a lwoer elements (so
instead of the entry title+link being in h2, try dropping it to an
h3?).
And of course, the always popular (and sodding difficult)...
get links to the entries as well as the homepage.
Additioanl ideas....
You may be able to pick up the referer.
This means that yo ucan tell where they are comming from as it carries
the URL.
If they are comming from Google, then it should have hte keywords in
the URL.
You may beable t odissect the URL, and pick out he keywords.
Then include a lbock of code to pull up relevant topics and display
those.
May want to double check on how to do that, and how to do it safely.
(Don't want to run into trouble for displaying different content to
bots/visitors).