How to search for submission and edit the same submission in form?

Hi, I'm doing a search on this; I have a primary key has the name Employee ID.

Different users can be able to retrieve the Jotform of each Employee ID and can update. When I start export the data, there

should be only one record per Employee ID and the record must have all the updates.

I don't know whether we can achieve this using Submission ID. 

Unfortunately it is not possible to load the form fields data form the existing submission and then update the same submissions. The only option available is to integrate your form with google spreadsheet which will send submission data to integrated google spreadsheet with edit link. You can share your integrated google spreadsheet with other users where they can search for an employee id and then click on the "Edit Link" of respective row and submit form again to update the same submissions.

The following guide should help you how to integrate form with google spreadsheet:   https://www.jotform.com/help/228-How-to-Integrate-Forms-with-Google-Sheets 

You can also add reports in form which will allow you to add "Edit Link" in the report.