Access Sub-Jars of Jar with Eclipse

I have a maven project and exported it as a single jar using Eclipse’s export to jar option. I created a new project and imported the jar by adding it to the classpath (add external jar). The jar seems to contain all sub dependencies:

Now, I want to use a class of such as subdependencie, e.g. form the commons package. However, I can not import it. How do I do that?