I Think. maybe your friend took 루라 for 루다 and there's a word "이루다" it is not a "루다".. anyway. 부를(rich) 이루다 -> achieve poverty or rich 꿈을(dream) 이루다 -> achieve a goal. so when you make your nickname and choose the last name as "이" and first name as "루다" Than your nickname could be 이루다. but when you choose last name as "미" than full name would be 미루다. it means put off "ST"

Maybe it is a mistake. I also couldn't understand why it means hope. Still,I like the name, so I will use it. :)

루라? i have never heard of that kind of words! im Korean:) maybe mistake?

According to this dictionary, I think "rura" might be just the transliteration of your name? I don't know if this is dialectal or some slang stuff, but I don't think it means “hope” in standard language because this dict is rather comprehensive. (But I'm not Korean, I can only give suggestion)