Keyword search is very slow on the GroupWise Client.

Using the Find feature with keyword and date in the GroupWise client on a mailbox containing a large number of e-mail takes minutes. Using author and date finds the message within a few seconds.

This is working as designed.

A keyword search with nothing checked in 'Item type' and 'Item source', will scan ALL sent AND received messages in their entirety (subject, content, etc) starting with the most recent. Time to find the correct message(s) will increase with the amount of messages the Find utility searches. Running a find using author and date will narrow the parameters of the search and bring faster results.

So the more messages you have in your in box, the more time it will take.  To speed up the process, be more specific and archive or delete unneeded messages helps as well.  If you archive mail, you can still search in it if you open it.  Not only speeding up searches, but speeding up the client as well.