refactor the code

@@ -55,21 +55,23 @@ func (w *Writer) execute(vals []interface{}) {
 		bulk.Add(req)
 	}
 	resp, err := bulk.Do(context.Background())
-
 	if err != nil {
 		logx.Error(err)
 		return
 	}
 
 	// bulk error in docs will report in response items
-	if resp.Errors {
+	if !resp.Errors {
+		return
+	}
+
 	for _, imap := range resp.Items {
 		for _, item := range imap {
 			if item.Error == nil {
 				continue
 			}
+
 			logx.Error(item.Error)
 		}
 	}
-	}
 }