Which is the exact Google Maps API, which I can use to send my geocoordinates to, and get teh closest larger location (think, village, town, city, region, etc)?
I need it also to be in proper international naming, because i am building a search engine, and I spotted that many locations remain unsearcheable unless they are typed with the exact specific characters used.
What you are looking for is called “Reverse Geocoding”. You can use this via the Google Geocoding API.