How to find similar Debit memo's using LIKE operation in soap API

Hi,

The Debit memo's will be created in the format XX_OrderNumber_YY_sequenceNumber.

So, when we create Debit memo in the fusion first we have the check if there are any other debit memo present in fusion with same order number. If present then the sequence number will be incremented by 1. For which I am trying to use LIKE operation to find the existing Debit memo is Fusion. But its not working.

If anyone know how to use LIKE operation in request query in xml to fetch Debit memos from Fusion. Also if any other operator can be used instead of LIKE operator? Please help here.