What is actually discharged?

I know all the dischargeable debts are elimiated after the Chapter 7 filing is approved. But are the dischargeable debts only those before the filing date or so-called pre-petition debts? As landlords, we can not even recover those post-petition debts like the rent and legal fee for filing motion in Bankrupty court and Eviction fee in district court? Are they discharged as well?

Thanks