A common question is if it is possible to connect multiple (chip) antennas together on a single circuit to achieve reception of multiple frequencies. The short answer is no and would take some engineering design considerations unless it is an already purpose-built antenna for the application. From impedance matching (matching networks), ground plane design, to circuit trace layout, it is not as easy to simply hook the antennas in parallel to the board to achieve this.
Additional Resources:
Infineon-AN91445 Antenna Design and RF Layout Guidelines Application Notes
Johanson Technology Chip Antenna Layout for 802-11 Applications
How to Properly Implement Chip Antennas
Return Loss vs. VSWR in chip antenna selection
DigiKey RF Antenna Selection