"Wij herkennen niets."
Translation:We do not recognize anything.
That's because niets means nothing. An alternative translation to the Dutch sentence would be "We recognize nothing". If the dutch sentence was 'wij herkennen niet', then it would be 'we do not recognize'. Of course these sentences are a bit awkward because they miss an object, and it would be more natural to say: "Wij herkennen het niet", "We do not recognize it".