diff --git a/src/EloquentBuilderTrait.php b/src/EloquentBuilderTrait.php
index d5a3d89..4df1d12 100644
--- a/src/EloquentBuilderTrait.php
+++ b/src/EloquentBuilderTrait.php
@@ -108,9 +108,9 @@ protected function applyFilter(Builder $queryBuilder, array $filter, $or = false
         // Destructure Shorthand Filtering Syntax if filter is Shorthand
         if (! array_key_exists('key', $filter) && count($filter) >= 3) {
             $filter = [
-                'key'      => ($filter[0] ?: null),
-                'operator' => ($filter[1] ?: null),
-                'value'    => ($filter[2] ?: null),
+                'key'      => (array_key_exists(0, $filter) ? $filter[0] : null),
+                'operator' => (array_key_exists(1, $filter) ? $filter[1] : null),
+                'value'    => (array_key_exists(2, $filter) ? $filter[2] : null),
                 'not'      => (array_key_exists(3, $filter) ? $filter[3] : null),
             ];
         }
@@ -281,7 +281,7 @@ private function joinRelatedModelIfExists(Builder $queryBuilder, $key)
             if ($relation instanceof BelongsTo) {
                 $queryBuilder->join(
                     $relation->getRelated()->getTable(),
-                    $relation->getQualifiedForeignKey(),
+                    $relation->getQualifiedForeignKeyName(),
                     '=',
                     $relation->getQualifiedOwnerKeyName(),
                     $type
@@ -298,7 +298,7 @@ private function joinRelatedModelIfExists(Builder $queryBuilder, $key)
                     $relation->getRelated()->getTable(),
                     $relation->getRelated()->getTable().'.'.$relation->getRelated()->getKeyName(),
                     '=',
-                    $relation->getQualifiedRelatedKeyName(),
+                    $relation->getQualifiedRelatedPivotKeyName(),
                     $type
                 );
             } else {