ANSWER:

It is not permissible to raise hands while making dua in salah. 

You can simply say dua sitting normally in tashahud. If you don’t get enough time behind the imam to make dua, you can take a few extra seconds(not more) after the imam says salam and make dua and then finish your prayer and you can always make dua in your voluntary prayers as well. 

 

As I came to know from your videos to make dua before tasleem, my question is, how is it possible while we are in jamath as we are suppose to follow the imam, and is it allowed to raise hands in dua before tasleem