I am wondering if there is a way in KoboToolbox to limit view/editing data for some users and let other users see all the data-set.
For example, I have a complaint form with non-sensitive and sensitive questions, for non-sensitive questions it is OK if all users I shared project with them to view/edit all data BUT if non-sensitive questions were answered only one user can see the content of it, others see nothing.
Welcome to the community! Would you mind looking over to the support articles on Row-Level Permissionshere and Managing permissionshere. It should guide you on sharing your data to specific users only.
Sorry to inform you that KoBoToolbox does not offer this feature. However you could make a features request by providing detailed information of what you wish to see in the future here.