diff --git a/src/app/shared/stores/global-search/global-search.state.spec.ts b/src/app/shared/stores/global-search/global-search.state.spec.ts
index dd78a40d0..e204398a9 100644
--- a/src/app/shared/stores/global-search/global-search.state.spec.ts
+++ b/src/app/shared/stores/global-search/global-search.state.spec.ts
@@ -262,6 +262,40 @@ describe('GlobalSearchState', () => {
 
       const params = mockGetResources.mock.calls[0][0];
       expect(params['cardSearchFilter[defaultKey][]']).toBe('default-value');
+      expect(params['cardSearchFilter[defaultKey][any-of]']).toBeUndefined();
+    });
+
+    it('should AND the default value with an any-of clause for an explicitly selected value', () => {
+      const { store, mockGetResources } = setup();
+
+      store.dispatch(new SetDefaultFilterValue('defaultKey', 'default-value'));
+      store.dispatch(
+        new UpdateSelectedFilterOption('defaultKey', [
+          { label: 'A', value: 'selected-value', cardSearchResultCount: null },
+        ])
+      );
+      store.dispatch(new FetchResources());
+
+      const params = mockGetResources.mock.calls[0][0];
+      expect(params['cardSearchFilter[defaultKey][]']).toBe('default-value');
+      expect(params['cardSearchFilter[defaultKey][any-of]']).toBe('selected-value');
+    });
+
+    it('should OR multiple selected values together via a single any-of clause', () => {
+      const { store, mockGetResources } = setup();
+
+      store.dispatch(new SetDefaultFilterValue('defaultKey', 'default-value'));
+      store.dispatch(
+        new UpdateSelectedFilterOption('defaultKey', [
+          { label: 'A', value: 'selected-value-1', cardSearchResultCount: null },
+          { label: 'B', value: 'selected-value-2', cardSearchResultCount: null },
+        ])
+      );
+      store.dispatch(new FetchResources());
+
+      const params = mockGetResources.mock.calls[0][0];
+      expect(params['cardSearchFilter[defaultKey][]']).toBe('default-value');
+      expect(params['cardSearchFilter[defaultKey][any-of]']).toBe('selected-value-1,selected-value-2');
     });
   });
 });
diff --git a/src/app/shared/stores/global-search/global-search.state.ts b/src/app/shared/stores/global-search/global-search.state.ts
index bc7bb2710..eb94222ea 100644
--- a/src/app/shared/stores/global-search/global-search.state.ts
+++ b/src/app/shared/stores/global-search/global-search.state.ts
@@ -327,7 +327,7 @@ export class GlobalSearchState {
     let hasCedarFilters = state.extraFilters.length > 0;
 
     Object.entries(state.selectedFilterOptions).forEach(([key, options]) => {
-      if (key in state.defaultFilterOptions) return;
+      if (key in state.defaultFilterOptions && options.length === 0) return;
       const filter = state.filters.find((f) => f.key === key) ?? state.extraFilters.find((f) => f.key === key);
 
       if (filter?.cedarPropertyIri) {
@@ -344,7 +344,10 @@ export class GlobalSearchState {
             filtersParams[`cardSearchFilter[${key}][is-present]`] = firstOptionValue;
           }
         } else {
-          filtersParams[`cardSearchFilter[${key}][]`] = options.map((option) => option.value);
+          const selectedValues = options.map((option) => option.value);
+          if (selectedValues.length) {
+            filtersParams[`cardSearchFilter[${key}][any-of]`] = selectedValues.join(',');
+          }
         }
       }
     });