let me understand: do you want to list events both from main search and subsearch or do you want to filter events from main search with the results of subsearch?
using the search you described, you reach the second solution and to add fields of the subsearch you have to use the join command.
So if inneroutput1 inneroutput2 inneroutput3 are three fields used to match the searches:
Join isn't a very performant command, so you could also use something like this:
(index=indexA sourcetype=outer) OR (index=indexB sourcetype=inner innerinput=abc)
| stats dc(index) AS num_ind earliest(_time) AS _time values(host) AS host BY outeroutput1 outeroutput2 inneroutput3
| where num_ind>1
| fields - num_ind