This is very much possible! You can do so using the 'Microflow call’ activity, available in your toolbox when you're editing a microflow. 

Hi Akshay,

Yes, you can call. This is one of the options in the action activity. Reference screenshots below:
 

You can select any of the microflow in your project after clicking select here.

Regards,

Sharad R K

HI,

Yes it’s possible and straight forward.  First create one microflow => Drag & Drop Activity and double click => Search for Microflow call and map your microflow.

Else, create one microflow => From the Toolbox => Drag & drop Microflow Call  

Yes, and it is encouraged if you can break the microflow up into reusable and testable pieces.

The documentation can really help you here explaining how to extract, use, and troubleshoot these sub microflows.

https://docs.mendix.com/howto/logic-business-rules/extract-and-use-sub-microflows