How to retrive a value of XML element in EAI Dispatch Rule?

After receiving the incoming XML message through JMS receiver, we send it to the EAI Dispatch Service (XMLHierarchy input arg). In the Rule Set, we must dispatch the message to the appropriate workflow according to the value of the specific XML element. How to set a search specification in a rule to retrieve the given value? That is, we have the XML element <ServiceName>Agreement.Get.OverdueOnDate</ServiceName> in the incoming message and the value "Agreement.Get.OverdueOnDate " must be retrieved. I tried to use "/ServiceName@Value", but it did not work.

Here is an example XML message sent to the EAI Dispatch Service: