Create a helper object that attach all the other three objects and use that helper object to design the page. Or use datasource microflows to retrieve the correct data. Last option would be to create one new object and create some hotfix microflow that fills that object so you can use that object for your form.
Thank you for the suggestion but I am pretty new to Mendix. So can you please let me know how can I create a helper object or use a datasource microflow. If possible can you please share the documentation in mendix.