POSTMAN API Development

I have Predefined Integration Point queries & was successful in using them to pull data. I need help extracting specific fields from those results (which can be really large) & exporting them to a text file. I need someone to create a functioning export that I can use to manipulate & run myself as I am unable to share data or code since everything is really secure. If you have an export API in it's most base form that you can set up according to the below results, please quote on the project. I'm just a little stuck and need something to push me on to the next level.

I am only pulling certain fields from these results so they could be anywhere in the results (payamt, name, address, city, state, etc)

<ServiceHist xmlns="http://www.xxxxx.com/svc-ro-hist">
<svc-ro-hist>
<dedmaxamt />
<payAmt>
<V Idx="1">246.97</V>
</payamt>

Many more fields are in the results......

End of the results below.

</svc-ro-hist>
<ErrorCode>0</ErrorCode>
<ErrorMessage/>
</svc-ro-hist>