Student or Learner
Sometime in english written and spoke I often see and listen "that" with meaning of "this". For example " that's right, look at that, that's all, that's my wife". I often use google translator and I seen this hidden meaning. I ask you now, How can i undertstand this hidden meaning? is there any rule?
Why do you think that "That's right" or "That's my wife" should be "This is right" or "This is my wife"? "This" and "that" are used for different purposes. but not always in the same way.
For example, if you are standing next to your car and you point to it, you would say "This is my car". If you were standing on the other side of a car park and you pointed at your car in the distance, you would say "That is my car".
If you were standing right next to your wife and introducing her to someone, you would say "This is my wife" but if you were pointing her out on the other side of a room then you would use "That's my wife".
We use "Look at this" and "Look at that" depending on context.
"That's right" is a little different as we are usually not pointing at a physical object. I would normally use the phrase to agree with or confirm something someone just said so I would say "That's right" to mean "What you have just said is right".
Please note my amendments to your post in red. Remember to capitalise the word "I" (first person singular) at all times, as well as capitalising proper nouns (English, Google).
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.