This idea is possibly covered by development on IDEAS-I-425 - Pre-population of Therefore Forms.
With a Wizard type eForm you can set mandatory fields which are used as filter values on a Table Lookup search configured on the second Wizard tab / page. Thus you can ensure the search will be filtered to show ONLY the record which matches their entered field values.
Unfortunately the user can subsequently 'toggle' the filter off by pressing the three dots button , which then shows all records in the search result list.
It would be useful if you could trigger the Lookup Table search automatically when entering the second page of the wizard, and if you were able to disable the three-dots button OR completely hide the Lookup Table field so the filter could not be removed. Such a configuration option could be added to the Lookup Table options.
Use cases for this are for e.g. employee on-boarding or school enrolment forms where the unauthenticated user has to provide several key search filter values, such as name, email and student number, and then other form fields are filled out with values already keyed into Therefore so they can change or accept them, and add new details.