This is a bit complex. I was trying to write an answer myself but I have a hard time explaining precisely all the cases, so I found this for you http://www.italianlanguageguide.com/pronunciation/syllabication.asp the last part specifically. It doesn't have all the rules I found in some italian texts but I suppose and hope it can do!

Well my question maybe is mentioned not clarely.I mean if After the vowel is another vowel how to divide syllable

I don't understand the question..