Czech Milena Velba I Need To Know If Anyone Knows The Origins And Meaning Of The Following Names: Avianna, Milena, Leighlin, Elio

I need to know if anyone knows the origins and meaning of the following names: Avianna, Milena, Leighlin, Elio - czech milena velba

I'm looking for websites that list the origins and meanings of names above. I find nothing in any of them ... I know that I found something in Hebrew Avianna for spring time. Milena and different backgrounds, such as Czech, Russian, Italian ... This means something like grace, but can not find what tonight. Not a single website is one of the names, watched the top.