Hi,
1. boost works with node scoped fulltext query (like contains(., 'income fund commentary')) - the query in your case is looking at fulltext on specific properties
2. the query breaks into (quite a few) union clauses due to OR to UNION optimization - sorting on score for such case doesn't work (OAK-7370 [0] / GRANITE-21031 [1]). Some useful documentation at [2], [3].
For (1), I would recommend modifying the query to do a fulltext query on node instead of each property - basically drop 3_group in query builder query and just put in 'fulltext = income fund commentary'
[0]: https://issues.apache.org/jira/browse/OAK-7370
[1]: https://jira.corp.adobe.com/browse/GRANITE-21031
[2]: http://jackrabbit.apache.org/oak/docs/query/query-troubleshooting.html#Ordering_by_Score_Combined_Wi...
[3]: http://jackrabbit.apache.org/oak/docs/query/grammar-xpath.html#ordering