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I am a volunteer in Italy since January 2017 and I have a national visa type D - Multi - 190 days. I'm staying in Italy 6 months until my project is finished in July 2017.
This is my first time in Europe, so I would like to make a trip to some other countries in the Schengen area at the end of June, before I return to my native country in the beginning of July. I'm afraid that I can't do it if I don't have a residence permit for Italy. They gave me an appointment on the 23rd of May at the Police department to apply for a residence permit, but I think it will be too late to get the decision (normally, it takes 2 or 3 months).
Can I use my visa to travel without residence permit? If it is possible, do I need prepare any document or paper to travel with my visa?