searching a text file for a player-input string

I have a GUI.TextField that allows the player of my project to enter information. This is then passed to a string upon hitting Return. I need this string to be checked against a text file of information and output a paired vector3. For example, the text file will have countries listed and their respective coordinates stored next to them in the format of Country/Coordinates. I need the string input from the player to be checked against the text file and if it is found, to then pass the Coordinates to a Vector3.

Any help with this would be greatly appreciated. :-)