Patentsview API Limitation

It looks like your query can't be q={"_and":[{"inventor_last_name":"smith"},{"inventor_last_name":"jones"}]} which would be looking for patents with a patentee named Smith and one named Jones which would typically be allowed by other systems or apis. As I right this, patft, the uspto's search system returns 335 such patents when in/smith and in/jones in their query language

The query returns no results though a sample of patents meet this criteria as illustrated by q={"patent_number":[8387443,9720067,8825466,9478429]} I'd guess that this is a feature, not a bug, something that would be difficult "fix" and applies to any of the fields like classifications where there can be more than one value per patent. Basically, you can't _and in the same field and expect results. This topic came up in the patentsview forum and they replied that it is not a limitation of the api but of the underlying data structure. It' is's still something I would like to be able to do and can do elsewhere.