Is there any way for one Arduino board to communicate with multiple sensors?
Yes you can ... however, how you transmit the sensor data? If wireless, you need some RF communication, and possibly a microcontroller like Arduino (or ESP) within each sensor module.

With nRF24L01 (2.4GHz) you can use 6 'slaves' (sensor modules in your case) to send data to the master (monitoring module).

Do things one by one: 


First make one sensor module
Than make the master to receive data
Than make the GUI screen
Than make the other five sensor modules