Søes was runner-up in the junior world championship in 2003 behind the Finnish Laura Hokka . The following year she completed her first European and World Championships, but without being able to place in the front field. Gradually, however, she managed to catch up with the world's best. In 2008 she came at the European and World Championships for the first time in individual races under the top ten. She even finished the 2008 World Cup season in fifth place. In 2009 she reached fourth place in Miskolc in Hungary, her best result so far at a world championship. In 2010 she became vice European champion in the middle distance, only beaten by the Swiss world class runner Simone Niggli .
