The tablets with dual operating systems, with Z8350 processor, whatever their brand, have a known failure in reading SD cards, first in Windows and then in Android. Once presented the failure there are some methods to reuse them, but they are not definitive. In your case, the card may simply not be formatted in an Android compatible format. Your card must be formatted in Fat32 and I advise you that, in case of being of greater capacity of the 32 Gb, make a partition in Fat32 of a size of 32 Gb and the rest of the space in a new partition formatted in NTFS for use in Windows .|
On the other hand, the connections of the micro USB port of the tablet is quite deep so you must ensure that the connector is inserted to the bottom, having to, in some cases, cut a millimeter of plastic around the connector.