A Google search for Arushma returns next to nothing. If this happens for a name it usually means that the name is unique, and that in turn usually means that somebody invented it.
A slim chance might be to find out that Arushma is just a very unconventional spelling of another, more common name, and then try to find a meaning for that name. But I don't have an idea how to spell this name differently. In German one would probably write 'Aruschma', but that name does not exist.
It seems to me that your only chance is to ask your parents about the name, and if that is not possible or they do not know either, put the matter to rest.
Anyway, also a lot of people with quite common names share this fate because for many names the meaning is simply unknown.
Rene
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