Looking for something? Check out the new universal search box at the top of the page. “Search Groups” allows you to search for groups you might want to join, or for specific messages within groups you are already part of.
 
To search for a group, start at the “Groups Home” page. Enter your query in the search box and click the “Search Groups” button. You’ll be presented with a list of all the groups that match your query.
 
To search for specific messages within one of your groups, select the group from your list of groups on the left rail.
Enter your query into the search box and hit “Search Groups”. You’ll be presented with a list of messages relevant to your query.
From there, if you need to narrow your search further you can use “Advanced Search”.
Clicking on “Advanced Search” on the top right of the Message list will open up additional search fields, allowing you to narrow your search by Author, Subject, Message or Date.
 
You can also search messages by message number.
To search by message number, select your group from the list and click on the “Messages” tab.
Click on the magnifying glass icon in the toolbar and enter the message number.

-Yahoo! Groups Team