Hi Jitendra,
Currently, we don't support working with multiple OData models in the Eclipse based OData modeler. However, in the future, we will provide a feature to cut & paste parts of an OData model between different model files which should address your need.
In the mean time, you may try merging different model files into one and try importing. I am sorry but we don't have anything else to offer at this time.
Regards,
Mustafa.