ANS: There are the two methods to get this trick work..
---> Click the Zynga Gift option as shown below..
---> Goto Game request option on home page of facebook and collect same gift's twice..
Step3: Go to farmville Gift box and check. you will find the same gift twice.
These trick is working 80% checkout farmers.
I have tried and got lots and lots of gifts..
Thanks to Zynga who made this thing possible..:P