Show fields in autocomplete but not use them in the search

I’m using an autocomplete and showing a number of fields from the results to give plenty of clarity but I don’t want all the fields to be used in the actual search.

Eg. If I have a list of names and their ages, my dropdown will show ‘Jon aged 21’ but I don’t want it to appear if someone types ‘21’ in the field.

How can I do this?