Okay; looks like Google inadvertently crawled/cached some of the pages for your Yahoo Group back when it might not have been set to Private/Restricted. First off, please make sure that the appropriate privacy options are set for your Yahoo Group, as follows:
On your group's main page, click Management | Control Panel.
Click Group Settings.
Next to "Group type," select your desired privacy as either Private or Restricted.
Done that, you may either wait for Google to automatically re-crawl and remove the group's pages from its search results (this will take upto two weeks), or if you want to expedite the process, you may submit a removal request for each of the page links that you want to be removed from the search results, using the following link:
Please note that even after you have submitted the removal requests, it will still take Google some time to manually drop off the pages from its search results - after they have verified that the contents of the pages are now set to private.
If you need any further assistance with this issue, please be sure to reply back using the box below.
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