No set off of losses against undisclosed income discovered by search, requisition or survey is permitted. A newly inserted provision bars set off of any loss, including brought forward losses, and unabsorbed depreciation against income deemed undisclosed income when such income is identified as a result of a search, requisition or survey. 'Undisclosed income' covers money, valuables, books entries or transactions found during those investigative actions that were not recorded in the books before the action or not disclosed to tax authorities before the action, and false expense entries discovered through those actions.