I donot understand the meaning of it. Does it mean I have to connect 120 or 130 ohm res. on both sides of both twisted pairs?

Hallo Mak,

if you would use an oscilloscope for your developement you would have noticed, why termination resistors are neccessary at both ends! Don't forget, you do not simply apply a static voltage to your cable, but you must struggle with electrodynamics, means, an electromagnetic wave is propagating through cable. And without correct termination at both ends there's a lot of catastrophal reflections (echoes), totally eroding logical levels.

By the way, termination impedance must match to characteristic impedance of cable! So, if you use 120 Ohm termination resistors, you must also use 120 Ohm twisted pair cable.
Analyze behaviour of some different cables, and of some grounding schemes of cable shield (grounding at one side only, or at both sides). Also, analyze performance of your RS485 interfacing, while connecting ground of shield to different ground potentials of your PCB. What you will see might be a bit shocking, right? Especially when cable becomes longer and longer...

If you have problems with RS485 interfacing, you could try to use slew-rate-limited transcievers. Then, missmatch of impedances is a bit more tolerated. But again, have a look with oscilloscope!!!

Bye,
Kai