Inconsistent parsing of pure negative queries inside brackets

[Rahul Verma]

Hi everyone,

While tracing a bug in one of our systems we notices some interesting
behavior from Solr.

These two queries return different results. I fail to understand why the
second query returns empty results just by adding brackets. Can you please
help us understand this behavior?
*1. Without Brackets:*
{ "responseHeader": { "status": 0, "QTime": 0, "params": { "q": "*:*", "
indent": "true", "fq": "-fl_monitoring_channel: 36 AND (title: salesforce)",
"wt": "json", "_": "1467637035433" } }, "response": { "numFound": 35541, "
start": 0, "docs": [...

*2. With Brackets:*
{ "responseHeader": { "status": 0, "QTime": 0, "params": { "q": "*:*", "
indent": "true", "fq": "*(*-fl_monitoring_channel: 36*)* AND (title:
salesforce)", "wt": "json", "_": "1467637344339" } }, "response": { "
numFound": 0, "start": 0, "docs": [] } }