Print form and subform

[zxmax]

I have a Form with subform , In my subform i have a Print option, that allow me to print a report ,

My problem is, every time run that report, it shows all the records, of the database for that subform ,
i would like it to print only the current Record,

Eg:

In my main form, i have "UserID" , "firstName" , "LastName", "PhoneNumber"
In my subform , i have some transaction related to the main form,

I was advised to use this
dim strWhere as string

strWhere="Ref=" & forms!myform!reffield
docmd.openreport "ReportName",asviewpreview,strWhere

For the line: strWhere="Ref=" & forms!myform!reffield
what is the Ref= ? and the reffeild ?

Is that the Feild ID name ?

Thanks for any input, or if you have any other solutions please advise

Thanks alot