I have tried following thing for Employee group:

[('user_id','=',user.id)]

But the problem is I couldn't submit the timesheet 

Odoo Access Error: Document :hr.employee type:read

I tried the following rule:

[('id', 'child_of', [employee.id for employee in user.employee_ids])]

to the Employee group. It works and I could submit the timesheet, but employee's manager records are visible in hierarchy which should be avoided.Please help me with the answer ! I am using Odoo 10