diff --git a/crates/omnigraph/src/exec/query.rs b/crates/omnigraph/src/exec/query.rs
index b1a834f4..a8ddf22e 100644
--- a/crates/omnigraph/src/exec/query.rs
+++ b/crates/omnigraph/src/exec/query.rs
@@ -1923,6 +1923,18 @@ async fn execute_node_scan(
             // Apply the structured IR filter via Lance's Expr pushdown.
             if let Some(ref expr) = filter_expr {
                 scanner.filter_expr(expr.clone());
+                // The filter must run BEFORE any ANN/FTS search on this
+                // scanner. Lance defaults to prefilter=false, which applies
+                // the filter to the search's top-k results — "you may get
+                // back fewer results than you ask for (or none at all)"
+                // (lance scanner.rs) — i.e. `limit k` would mean top-k of
+                // the whole table, silently starved by a selective filter.
+                // One flag governs both the vector and FTS sources, and it
+                // is unused by plain scans, so setting it whenever a filter
+                // is present is safe. Prefiltering also re-enables scalar-
+                // index acceleration for the predicate (Lance gates
+                // use_scalar_index on prefilter when a nearest is present).
+                scanner.prefilter(true);
             }
 
             // Apply FTS queries from hoisted search filters (search/fuzzy/match_text in match clause)
diff --git a/docs/user/search/index.md b/docs/user/search/index.md
index 280e9e86..1f0b12ad 100644
--- a/docs/user/search/index.md
+++ b/docs/user/search/index.md
@@ -20,6 +20,10 @@ rank).
 - `nearest()` requires a `limit`. The query vector is resolved from the param map,
   or embedded from a text input at runtime via the configured
   [embedding client](embeddings.md).
+- Match filters apply **before** the search: combining a `match` predicate with
+  `nearest()` (or `bm25()`) returns the top-`limit` of the *matching* rows —
+  never a post-filtered remainder of the global top-k. A selective filter
+  narrows the candidate set; it cannot starve the result count.
 - Scores and ranks propagate as ordinary columns, so you can `return` a score and
   `order` by it.