Yes your mother can sponsor your trip.
She would have to include a letter saying she will pay your expenses, and also her own bank statements showing that she is rich enough that giving you money for a tourist trip is not a problem for her. Details can be found here. (Thanks Traveller)
You should also be aware that you have to address the issue of you bank statement not reflecting your true expenditures. Without addressing this it will not help to have someone sponsor you. See other questions on this site and this guidance for how to address this problem.
You should be aware that after two refusals it becomes increasingly difficult for you to be accepted even when you address the issues. Repeated applications after refusals make it look like you are desperate to get to the UK, which makes them think you have some reason other than tourism.
You might want to consider visiting a country other than the UK for your tourism.