If What material fact not been disclosed is not clear in order rejecting the objections issue of notice u/s. 148 is invalid

What material fact has not been disclosed by the assessee is not clear in order rejecting the objections issue of notice under section 148 is invalid. The proviso to section 147 of the said Act imposes an injunction on the revenue authorities prohibiting them from taking any action beyond the said period of four years unless (i) any income chargeable to tax has escaped assessment for such assessment year, (ii) by reason of the failure on the part of the assessee (a) to file a return under section 139 of the said Act or in response to a notice issued under sub-section (1) or section 147 or sect...