It is not possible to adhoc search data directly in Activity view with complex combination of "AND" and "OR" operator in NextGen version.
E.g. Search all data in activity view where
(ItemState = Outstanding
Grid
AND Value Date > Today -1)
OR
(ItemState = Matched
AND Break Reason = Partial Settle
AND Post Date > Today -5)
User can perform this kind of search in classic version. However not possible for consumer to perform this kind of adhoc data searching within activity grid.
It is better if filter criteria features in Data Groups can be extended to Search in Activity Grid.