diff --git a/geonode/indexing/api/filters.py b/geonode/indexing/api/filters.py
index 9e362e964f5..e057d5613a3 100644
--- a/geonode/indexing/api/filters.py
+++ b/geonode/indexing/api/filters.py
@@ -9,7 +9,7 @@
 from rest_framework.filters import BaseFilterBackend
 
 from geonode.indexing.models import ResourceIndex
-from geonode.metadata.multilang.utils import get_2letters_languages, get_pg_language
+from geonode.metadata.multilang.utils import get_2letters_languages, get_pg_language, get_default_language
 
 
 logger = logging.getLogger(__name__)
@@ -45,18 +45,27 @@ def validate_lang(search_lang):
         if search_index not in settings.METADATA_INDEXES:
             raise serializers.ValidationError(f"Unknown index '{search_index}'")
 
-        search_lang = request.query_params.get("search_lang", None)
-        if search_lang:
-            search_lang = validate_lang(search_lang)
-        if not search_lang:
-            search_lang = get_language_from_request(request)[:2]
-            search_lang = validate_lang(search_lang)
-
-        lang_filter = Q(lang__isnull=True)
-        if search_lang:
-            lang_filter = lang_filter | Q(lang=search_lang)
-
-        pg_lang = get_pg_language(search_lang)
+        if any(field in settings.METADATA_INDEXES[search_index] for field in settings.MULTILANG_FIELDS):
+            # We have at least one field in the index that is multilang
+
+            # first option: get a language as query param
+            search_lang = validate_lang(request.query_params.get("search_lang"))
+            if not search_lang:
+                # 2nd option: check standard config: http headers, cookies
+                lang_from_request = get_language_from_request(request)
+                if lang_from_request:
+                    search_lang = validate_lang(lang_from_request[:2])
+            if not search_lang:
+                # fallback: just take the default lang
+                logger.info("search language not found, forcing default")
+                search_lang = get_default_language()
+
+            pg_lang = get_pg_language(search_lang)
+            lang_filter = Q(lang=search_lang)
+
+        else:  # the index has no multilang entry
+            pg_lang = get_pg_language(None)
+            lang_filter = Q(lang__isnull=True)
 
         queryset = queryset.filter(
             pk__in=Subquery(
diff --git a/geonode/indexing/manager.py b/geonode/indexing/manager.py
index aec114115c5..9a34176a89f 100644
--- a/geonode/indexing/manager.py
+++ b/geonode/indexing/manager.py
@@ -53,7 +53,7 @@ def update_index(self, resource_id, jsoninstance: dict):
 
             if all(field in non_ml_fields for field in index_fields):
                 # this index is not localized
-                pg_lang = multi.get_pg_language(multi.get_default_language())
+                pg_lang = multi.get_pg_language(None)
                 logger.debug(
                     f"Creating non localized index - resource:{resource_id} index name:{index_name} default lang:{pg_lang}"
                 )