I like the name. It sounds really pretty. I don't know of it myself. I couldn't tell you the meaning or history. It is a possible made up name. I know of the english name
Doria (this is the feminine form of
Dorian) also, (possibly derived from the name
Dora). The name
Doria derived from
Dorian which came from the Ancient tribe the Dorians.
Diora could possibly be derived from these names. Its not certain but only an educated guess. If you click on the name
Doria link in this post you can read more on this name. Maybe you can find out if Diora is a variant of this name or not.
But I do like it. Its very pretty :)