If someone said  Nasýlsýnýz?   and i replied with iyiyim, teþekkür ederim  how would i say ´and you?´   would it be: sýnýz?

"ya siz ?"  you can ask like this.

ok thanks. so is  sýnýz  incorrect?

 Yes. It just means "you...."

"-sýnýz" is just the suffix, you cannot use it alone.

You can say

-Ya siz?

-Siz?

-Siz nasýlsýnýz?

thank you to all of you