Hello, thanks for the replies..
I feel that my pup knows that what he did is wrong, he will hide after he urinate on the sofa or potty near the study table. i realise that he likes to potty near the study table,, although, he knows it is wrong.. he has that guilty look on his face and will start hiding after he did that. why keep doing it? is it because my cat's toilet is nearby and he wants a stronger smell than the cat? really puzzles me.