Reading NFC tag from a slightly longer distance
RFID tags such as these depend on the antenna to not only receive and send the signal, but the antenna must inductively capture enough of the power from the transponder to wake up and transmit back.  This means that the orientation of the antenna, which in this case is just a spiral piece of foil, must be perpendicular to the "lines of flux" of the transmitter's local magnetic field.  If they are parallel, you are out of luck regardless of distance.

Depending on what you are trying to do, you might experiment with three tags glued together such that they face in three axes - chances are that one or two will be able to respond.  A more powerful transmitter increases your chances when the angle is not ideal.  Good luck!