You flashed it with a Chinese version ROM, which is only meant for use in mainland China, where Google is basically outlawed. You either need to re-flash it with the appropriate A858 international version ROM, or find a way of rooting it and then install the Google Mobile Services(GMS) stuff as system yourself....good luck with the latter.
Where did you download the Chinese ROM from? needrom.com only has the Chinese version ROM for this device. You may need obtain the correct international ROM from Lenovo, or get Lenovo service to do it.