You probably are creating an unusual namspace scheme. It appears you are namespacing every class from your module differently. You should namespace your code within your module only, like so:
// Adding Onur to the namespace prevents any future namespace collisions.
<?php namespace Onur\Facebook;
After creating your namespace you should add all classes that are outside of your namespace that you want to use as followed.
use Eloquent, Input, Validate, Etc;
This prevents you from adding a \
in front of every class instance, making your code hard maintain and prone to errors. It also gives you a good overview on all the classes you are using in the current class.