Task: Find a new book recommendations

n8n workflow:
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Please update your n8n workflow with a different subject.</p>\n\n<p>A list of all available subjects can be found at <a href=\"https://openlibrary.org/subjects\">the Open Library</a>.</p>","options":{},"subject":"=Book not found in {{$node[\"Check Book Count\"].json[\"name\"]}}","toEmail":"john.doe@example.com","fromEmail":"john.doe@example.com"},"credentials":{"smtp":"Gmail Creds"},"typeVersion":1},{"name":"Send Book Email","type":"n8n-nodes-base.emailSend","position":[2030,330],"parameters":{"html":"={{$node[\"Book Recommendation\"].json[\"msgBody\"]}}","options":{},"subject":"={{$node[\"Book Recommendation\"].json[\"msgSubject\"]}}","toEmail":"john.doe@example.com","fromEmail":"john.doe@example.com"},"credentials":{"smtp":"Gmail Creds"},"typeVersion":1}],"active":false,"settings":{},"connections":{"Set Subject":{"main":[[{"node":"Retrieve Book Count","type":"main","index":0}]]},"Check Book Count":{"main":[[{"node":"Select Random Book","type":"main","index":0}],[{"node":"Send No Book Email","type":"main","index":0}]]},"Filtered Book Info":{"main":[[{"node":"Create Author String","type":"main","index":0}]]},"Select Random Book":{"main":[[{"node":"Retrieve Basic Book Info","type":"main","index":0}]]},"Book Recommendation":{"main":[[{"node":"Send Book Email","type":"main","index":0}]]},"Retrieve Book Count":{"main":[[{"node":"Check Book Count","type":"main","index":0}]]},"Create Author String":{"main":[[{"node":"Book Recommendation","type":"main","index":0}]]},"On clicking 'execute'":{"main":[[{"node":"Set Subject","type":"main","index":0}]]},"Every Friday at 11:00 AM":{"main":[[{"node":"Set Subject","type":"main","index":0}]]},"Retrieve Basic Book Info":{"main":[[{"node":"Retrieve Detailed Book Info","type":"main","index":0}]]},"Retrieve Detailed Book Info":{"main":[[{"node":"Filtered Book Info","type":"main","index":0}]]}}}