queries like the above fetches everything as it searches the first email in every conversation (which would not obviously have any traces of [email protected]) and then returns the entire conversation in the search result, which is not the desired output.
I found a three step solution.
Step 1: Search all conversations that received a reply from [email protected] using the below search query
to:[email protected] from:[email protected]
Step 2: Label all the search results as "replied" using the gmail UI
Step 3: Search for conversations that are NOT labelled as "replied"
to:[email protected] -label:replied
I got the desired results :)