question

You could refer to the code below to get all bundles in your stores.

 void GetBundlesInStores()
 {
     PlayFabEconomyAPI.SearchItems(new SearchItemsRequest
     {
         //get store list
         Filter = "type eq 'store'"
     }, re1 =>
     {
         foreach (var store in re1.Items)
         {
             Debug.Log("StoreId:" + store.Id);
    
             PlayFabEconomyAPI.SearchItems(new SearchItemsRequest
             {
                 //filter bundles in store
                 Filter = "type eq 'bundle'",                    
                 Store=new StoreReference { Id=store.Id },
             }, re2 =>
             {
                 foreach (var bundle in re2.Items)
                 {
                     Debug.Log("BundleId: " + bundle.Id);
                 }
             }, er2 =>
             {
                 Debug.Log(er2.GenerateErrorReport());
             });              
         }
     }, er1 =>
     {
         Debug.Log(er1.GenerateErrorReport());
     });
 }