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Query understanding guides
9 published guides. Start with Query understanding.
Everything that happens to a query before retrieval: cleaning, expansion, rewriting and intent detection.
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Understand it1 guides
How it works7 guides
ExplainerQuery expansionClassic and LLM-based query expansion, how each widens recall, and how to stop it drifting off topic.ExplainerQuery rewritingHow rewriting vague or conversational queries before search improves results, with prompts and pitfalls.ExplainerHyDE (hypothetical document embeddings)HyDE has an LLM write a fake answer and searches with its embedding. How it works, when it helps, and the paper.ExplainerMulti-query retrievalGenerating several phrasings of one question and merging the results to raise recall.ExplainerQuery decompositionSplitting multi-part questions into sub-queries, retrieving for each, and recombining.ExplainerQuery intent classificationDetecting what a searcher wants so the system can route to keyword, semantic or filtered search.ExplainerTypo tolerance and spelling correctionHow embeddings and spelling correction handle misspelled queries, and where they fail.