SETFILTER how to apply the filter which more than 20 chars?

Hi Expert.


I just got a pb. which I need to find the return order No from the posted credit memo .

what I did like this.

   1. Find the related "Return Receipt No." from Sales credit memo line.

   2. find the related "Return Order No."  from sales receipt line .

   3. find the related return Order.


the relationship is :

1 posted creidt memo has many lines, many lines has many sales receipt line . , and many sales receipt line . has many return orders.

I use a text variable to record the last get return orders. and last setfitler("No.",textvar)

But I fond the textVar of setfilter has the 20 chars limit.

How can I do it?

Thanks in advance.