1. Tools--> Preferences --> Transactions (Use Multiple Change Addresses check box) what means? I already have checked the above that is Use Change Addresses and looking in tab Addresses I can see Receiving and clicking left arrow besides Change there are six addresses. So what is the difference between them?
2. Tools--> Preferences --> Transactions --> Coin Selection: (Privacy and Priority). What is the difference using first or second one.
If someone has the same confusion with me and has found the solution maybe wants to drop a line or post a link.
You can just hover your mouse pointer over the change addresses option or click the coin selection and it'll give you very good explanations on what those options are.
Thank you very much Jhanzo. It was so easy but I was not patient enough to understand it. Really helpful. I lock topic and I hope that would be useful for someone else like was for me.