Rebuild and Reindex the TextBase. You can do this for multiple TextBases at the same time, however please note that the TextBase will be offline and inaccessible until these operations are finished. If you rebuild a TextBase without reindexing it afterwards, you may still see odd search results until the TextBase has been reindexed.
From the MultiTrans Client navigate to Manage TMs > select the TextBase > Rebuild:
This may take a while to complete depending on the number of TextBases selected and how big they are. In the Scheduled Operations window, click the Refresh button occasionally to check the progress of the Rebuild until it is "Finished":
Once the Rebuild is done, you should also Reindex it via Manage TMs > select the TextBase > Reindex:
As with the previous Rebuild operation, click Refresh occasionally until the status of the Reindex operation is "Finished":