1. Launch QPS Connect Client.
2. In the Search Results palette, choose Customize from the drop-down menu on the right end of the toolbar.
3.
Check Show ToolTips on Toolbars.

Background
The information about 'Show ToolTips on Toolbars' is saved in the file ApplicationPreferences.dat i.e.available at the following location :

Windows 7
C:\Users\{Current User}\AppData\Roaming\Quark, Inc\Quark Publishing System\8.1.4 (or 8.1.6 or 8.1.6.2 or 8.5)

Windows XP
C:\Documents and Settings\{Current User}\Application Data\Quark, Inc\Quark Publishing System\8.1.4 (or 8.1.6 or 8.1.6.2 or 8.5)