It is a matter of relative distance. "Right here" is closest. "Here" means close; at the same place where I am. "There" means a little farther away. "Over there" means even farther. "Way over there" means farther still. If I am sitting in my car, I might say: "The steering wheel is right here." "The headlight switch is here." "The radio is there." "The glove compartment is over there." "The maps are way over there in the passenger door's map pocket; I can't reach them." The distances can't be measured in centimeters or meters. They are vague and they are on whatever scale the speaker is thinking about. The mailbox is right here, in front of the pharmacy. The pharmacy is here. The supermarket is there. The police station is over there, across the street. The bank is way over on the other side of town.

Actually 'over' is similar 'on'. So, when someone is pointing out that an object is over there then it means that the object is on that particular area and area can be anything home, market,room or part of the room or anything.

Hi there, If you say that something is 'over there' it indicates that there is some distance between the speaker and the object that you are pointing out. You can say that something is 'over there' if it is on the opposite side of the room for example. Also, if you are pointing out a building from a long distance you can use 'over there' If something is not a long distance away from the speaker you should just use 'there'. Also, if you are not sure then it is better to use just 'there'.

中文就是“在那儿”