This package contains the Xfce settings plugin and the utility files for libexo-0.3-0 which are:
exo-csource
exo-desktop-item-edit
exo-mount
exo-open
exo-preferred-applications
exo-eject
exo-unmount
The discripton for libexo on Debian packages is
libexo is a library for Xfce that contains a bunch of additional
widgets and a framework for editable toolbars (an improved version of
the framework present in GNOME), light-weight session management
support, functions to automatically synchronize object properties
(based on GObject Binding Properties) and several miscellaneous
utility and helper functions for application developers.
While Xfce ships with quite a few libraries that are primarily
targeted at desktop development, libexo is targeted at application
development, with a focus on applications for Xfce.
As for WARNING:the packages could not be authenticated please see this question with a good answer
None of this really matters, you can't search Google like that.
The package googlecl allows some functionality in terminal but not search, only
picasa, blogger, youtube, docs, contacts, calendar, finance parameters.
To search online from a terminal please see this question.