No set off of undisclosed income discovered in search or survey prevents loss offset against such identified income. Section 79 disallows set off of losses against undisclosed income brought to tax following a search under section 132, a requisition under section 132A, or a survey under section 133A (excluding TDS/TCS surveys). 'Undisclosed income' covers money, valuables, or entries not recorded in the books or not disclosed to tax authorities before the date of search/requisition/survey, and expense entries found to be false that would not have been detected absent the search, requisition or survey.