“This guide covers the integration of OpenAI's Large Language Models (LLMs) with Pinecone (referred to as the OP stack), enhancing semantic search or 'long-term memory' for LLMs. This combo utilizes LLMs' embedding and completion (or generation) endpoints, alongside Pinecone's vector search capabilities, for nuanced information retrieval.   ”   here what does the word "nuanced" mean in Chinese?