searchRecords() API method with CRM

searchRecords() API method with CRM

It seems that I cannot use the searchRecords() API method with the Campaign field "Campaign Owner".

This is what my criteria paramater looks like: &criteria=(Campaign Owner:owner name)

I get this response: 

Error Code: 4832
Message: API call cannot be completed as the Criteria parameter contains unsupported fields

Why can I not search over Campaign Name? It's a very relevant field to the campaign module ( Campaign Module Fields). Is this a bug?

Urgent help requested please