Query rewriting transforms a user query into alternative phrasings that better match the terminology and context of target documents. It addresses a common vector-retrieval failure: semantically important documents may be missed when query and corpus language differ. section 3.0
Use query rewriting to improve retrieval when:
- The query embedding does not align closely with documents containing the needed information. section 3.0
- The user’s intent is expressed differently from the language used in information-rich documents. section 3.0
- The retriever needs contextual summaries, paraphrases, or hypothetical questions alongside exact text. section 3.4
Two rewriting strategies
Hypothetical document retriever and step-back prompting reformulate the retrieval input so it better bridges user intent and document content. section 3.0 section 3.4
Figure 3.1 Query rewriting by using the step-back technique to increase the vector retrieval accuracy
Shows how step-back rewriting can increase vector-retrieval accuracy. section 3.0




