How to display custom DFF conditionally in Details section when creating a job requisition

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How to display custom DFF conditionally in Details section when creating a job requisition

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The requirement is to display the custom DFF conditional on whether the posting location is within the US and if the job family falls within Engineering. I was thinking to use an EL expression, but there are two issues with this. The DFF component within the Details section is grouped together and not separated by the individual DFFs. If this component is grouped together, how can I add the EL expression specific to only one DFF? Second issue is how to write the EL expression to satisfy requirement.