I have 10 test cases and want to run all test cases with 5 VUs each simulteneously, how i suppose to do that?
You can easily do that. If you would like to exactly run 5 VU's for each test cases (ie virtual user profile) you could create 10 different populations and include each of your test cases then set a 5VU's load policy for each population.
You could also create only 1 population and put inside your 10 test cases with a 10% percentage each.
Then set a 50 VU's load policy for that population.
For more details, i would suggest you to look at the NeoLoad documentation here