What is semantic search? Finding relevant material beyond exact wording
Understand semantic retrieval through return-related paraphrases, distinguishing embedding search from semantic reranking, with checks for codes, negation, and freshness.
Understand the concept
Semantic search finds meaning-related material beyond exact keywords. Implementations can use embeddings or semantic reranking, and vendors use the term differently. Similar meaning does not establish applicability; identifiers and negation can still be confused and require source checks.
Paraphrases can retrieve useful and neighboring topics
A request to send back an unsuitable item can match return instructions despite different wording. Exchanges are nearby in meaning but may have different rules. Inspect passage scope rather than treating the top similarity as the answer.
Sentence Transformers distinguishes matching forms, including short queries against longer passages. Sentence similarity capability does not guarantee retrieval suitability. This explanation includes no built index or measured comparison.
Distinguish vector retrieval from semantic reranking
Vector retrieval searches compatible query-document embeddings; semantic reranking reorders existing candidates. Microsoft’s semantic ranker is the latter and should not be treated as the universal semantic-search pipeline.
Reranking cannot recover unseen candidates by itself. Missing vector results can stem from chunks or stale indexes. Keep stage outputs and source passages to distinguish candidate generation from ordering problems.
Exact identifiers and access scope need separate controls
Product codes differing by one letter can be semantically similar but refer to different instructions. Combine lexical matching or metadata and test fixed cases. Relevance does not grant access to unauthorized material.
Evaluate paraphrases, related-but-inapplicable content, and stale-version matches. This is a test design without claiming universal superiority over keyword search. Choose by coverage and runtime requirements, not technology labels.
Checked sources
These sources support the concepts and methods described here. Examples and test scope are labeled separately; check the version of the tools you use.