I have just applied for ews certificate but it take much time can I use a receipt of ews in mht cet document verification

You can produce that but it would be more convenient if you can get a written recommendation from your District Magistrate/Deputy Magistrate / Police Commisionerate , it would be more convinving for them because all the above mentioned officers are Grade A gazetted Officers and legally the document itself will get attested as it will state that you have applied for EWS and you satisfy the criteria but due to its long process of issue , you wont get it.

I hope my answer helps. All the very best for future endeavors!