I am using a reference field in a catalog form.

[taahamushtaq]

I am using a reference field in my catalog form. It is referring to  CMDB Business application table.
I want to only search variables with name and no duplicate records should be included.

[Mark Manders]

You can use a reference qualifier to only show the ci's where name is not empty. 

If you see duplicates, that means that you have more than 1 ci with the same name. It doesn't really make sense to have those, if you need to select them, but excluding is weird as well. You need to select a record and upfront you never know which of the duplicates is the correct one. 

In case there's a status difference between the correct and the wrong ones, you can add the status to the reference qualifier as well.