Question: I'm looking for something people from rural area would use, especially when they refer to that person's inability to adapt to the country life.

Answer: 
(D\*\*ned) urbanites. Or if the rural area happens to be hilly or mountainous, flatlanders.
**city boy/girl** (disparaging when used to describe an adult)

[Oxford dictionaries](http://www.oxforddictionaries.com/us/definition/american_english/city-boy)

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> A boy or man who is a native or inhabitant of a city, or who has urban tastes or manners.
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