/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String input = "melanie rugullies eching trägt dirndl darüber das volksfestmadl stadt freising dürfen begeistern für tanzsport ";
	    //does not work
	    input = input.replaceAll("( dürfen )", " ");
	    input = input.replaceAll("(\\sdürfen\\s)", " ");
	    input = input.replace(" dürfen ", " ");
 
	    //works ...
	    input = input.replaceAll("(\\sdarüber\\s)", " ");
	    input = input.replaceAll("(\\smöchte\\s)", " ");
	    //input = input.replace(" dürfen", " "); //works but is not desired ...
	    System.out.println(input);
	}
}

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