One-to-Many Relationship type is not showing in Studio

I am working in Sugarcrm 7.8 I am trying to create a relationship between contacts and my custom module example myorder but its not showing in type field when I select my custome module in `Related Module' 

I couldnt able to find any doc which explains such situation. How i can make a one-to-one relationship through studio when its not showingup. I really dont like to create through code as it breaks operations while we try to retrive report. If i work through studio its fine.

Any how i tried creating the follwing files to see if it shows any relationship.


But it creates a new relationship via code.

Has anyone been able to achieve anything similar?