@Varun R
After split text processor use extract text processor and add new property with matching regex, then the extracted attribute will be added as the flowfile attribute.
Example:-
After split text you are having each address in a flowfile as like this http://aaa.com/q="bigdata"≈i_key="", now you want to know which query param value(ex:bigdata) has been used.
Then use extract text add new property
query_values
q="(.*?)"

output flowfile:-

Once the flowfile processed by extract text processor it matches the regex and adds the attribute query_values to the flowfile.
By this way you are going to know which query param values are used to get response.
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