Let's say for example, you have completed your B.Sc and you also completed your M.Sc from India in some specialisation.  You want to pursue another M.Sc but from abroad. You can do that. This is because you are applying for Masters based on the same Bachelor's degree that you have obtained. If you fulfill the eligibility criteria and can secure a seat in Master's abroad, there should not be any reason as to why you cannot study your Masters again abroad. It will be a dual Master's .