In nature, energy sources originates from the fire (agni). Fire element is recommended here to get a requisite relief from the missing south-east corner. You need to very carefully provide a fire place between east and south side.
Placing toilet or a kitchen in the north east or south west creates a vastu dosha polluting a positive energy in the premises.
Sometime, people with the negative approach may disturb your personal space, which could also be a reason for the negative environment.
Space clearing with Vastu will work as a shield against the negative energies or Urja.