I haven't been able to do a successful search using that endpoint either, dunno if it's actually working or if it expects something else.
I've used these two successfully
/api/v2/knowledge/knowledgebases/{knowledgeBaseId}/documents/search
/api/v2/knowledge/knowledgebases/{knowledgeBaseId}/documents/search/suggestions
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Jan Heinonen
Contact Center Specialist
GlobalConnect AB
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