When you assign a role to an employee, if in the Visible Roles you have not checked any box, this user will only see those documents created by the same, for your employee to have access to documents created by other users, you must enter the role assigned to the user who cannot see the documents, in the first section "Visible Roles" you must have selected the role of the employee who creates the documents, otherwise even if they have permission they will not be able to view them.
From your profile go to Settings > My company > Roles. Enter the role you want to configure and in the Visible Roles section, check the boxes for the role of the employees who create the documents.
Your user can now see the documents he/she needs.