Virus?
 

I got a new plant without checking the leaves which showed a sign of Cymbidium mosaic virus infection.
Could you please give me some ideas about it?
Thanks in advance.

I'd try to take it back to the grower for a replacement. If they will not and if it is CymMV it should be destoryed so it does not spread to others in your collection.

Thanks, Ted. I have separated the plant and I will send a sample to exam what kind of disease it is.