> For the complete documentation index, see [llms.txt](https://docs.flowiseai.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flowiseai.com/integrations/langchain/retrievers.md).

# Retrievers

***

Retriever nodes return documents given an unstructured query. It is more general than a vector store. A retriever does not need to be able to store documents, only to return (or retrieve) them.

### Retriever Nodes:

* [Cohere Rerank Retriever](/integrations/langchain/retrievers/cohere-rerank-retriever.md)
* [Embeddings Filter Retriever](/integrations/langchain/retrievers/embeddings-filter-retriever.md)
* [HyDE Retriever](/integrations/langchain/retrievers/hyde-retriever.md)
* [LLM Filter Retriever](/integrations/langchain/retrievers/llm-filter-retriever.md)
* [Multi Query Retriever](/integrations/langchain/retrievers/multi-query-retriever.md)
* [Prompt Retriever](/integrations/langchain/retrievers/prompt-retriever.md)
* [Reciprocal Rank Fusion Retriever](/integrations/langchain/retrievers/reciprocal-rank-fusion-retriever.md)
* [Similarity Score Threshold Retriever](/integrations/langchain/retrievers/similarity-score-threshold-retriever.md)
* [Vector Store Retriever](/integrations/langchain/retrievers/vector-store-retriever.md)
* [Voyage AI Rerank Retriever](/integrations/langchain/retrievers/page.md)


---

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## Querying This Documentation
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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

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