RyanAir allows you to take a handluggage and a small bag with you on the plane. The policy for Vueling is less specific. Based on this page - http://www.edreams.com/blog/luggage-restrictions-by-airline/, it says that you can also take:
In addition, each passenger is allowed to carry one of the following items at no additional charge: a small purse or wallet, a coat or travel blanket, a laptop, or camera.
The official website at http://www.vueling.com/en/vueling-services/prepare-your-trip/luggage does not mention anything about another bag / laptop etc.
Do you think I can take with me a small bag as well, like a small backpack?