You have to show your actual income in income tax return... if your income is more and you show it less in income tax return, than its chance that you will got income tax notice..
143(1) notice is given to a person if there's is a mismatch between the declaration of data by the person and the data available with the IT department ,or in case of wrong declaration of investment or error in tds and alll
there are arithmetical errors. an incorrect claim disallowance of loss claimed disallowance of expenditure indicated in the audit report but not taken into account in computing the total income . disallowance of deduction claimed under section 10AA,80IA,80 IAB,80 IC,80 ID.