Deskbar Applet is one of the most useful utilities in ubuntu which provides an ability to search programs,dictionary,files,address book,Yahoo,web history, and so forth in your computer.
To install the Deskbar,run following command in terminal:
sudo apt-get install deskbar-applet
Right click anywhere on panel and select ‘add to panel’,
Find the Deskbar and click on Add button
Using deskbar to search something like this.