diff --git a/services/competitor_price_feeder.py b/services/competitor_price_feeder.py
index 2b0acdd..cc79e39 100644
--- a/services/competitor_price_feeder.py
+++ b/services/competitor_price_feeder.py
@@ -145,7 +145,11 @@ def _build_search_keywords(momo_name: str) -> list:
         elif parsed.keywords:
             terms.append(" ".join(parsed.keywords[:4]))
     except Exception:
-        pass
+        logger.debug(
+            "[Feeder] ProductNameParser failed while building search keywords; "
+            "fallback to cleaned product name",
+            exc_info=True,
+        )
 
     return _dedupe_terms(terms)
 
diff --git a/tests/test_competitor_match_attempts_persistence.py b/tests/test_competitor_match_attempts_persistence.py
index 038524f..bd042a0 100644
--- a/tests/test_competitor_match_attempts_persistence.py
+++ b/tests/test_competitor_match_attempts_persistence.py
@@ -1,4 +1,5 @@
 from pathlib import Path
+import logging
 
 
 ROOT = Path(__file__).resolve().parents[1]
@@ -26,3 +27,19 @@ def test_competitor_feeder_persists_all_match_attempt_outcomes():
     assert "best_match_score" in migration
     assert "error_message" in migration
     assert "idx_comp_match_attempts_sku_source_time" in migration
+
+
+def test_competitor_feeder_logs_keyword_parser_fallback(monkeypatch, caplog):
+    from services import competitor_price_feeder
+    from services.price_comparison import ProductNameParser
+
+    def broken_parse(self, *_args, **_kwargs):
+        raise RuntimeError("parser unavailable")
+
+    monkeypatch.setattr(ProductNameParser, "parse", broken_parse)
+    caplog.set_level(logging.DEBUG, logger="services.competitor_price_feeder")
+
+    terms = competitor_price_feeder._build_search_keywords("理膚寶水 B5 修復霜 40ml")
+
+    assert terms
+    assert "fallback to cleaned product name" in caplog.text