Using the following text, a street in Hannover is not found using maps.openrouteservice.org or the API playground:
https://api.openrouteservice.org/geocode/search?api_key=[key]&text=carl-neuberg-straße%20hannover
“carl-neuberg-straße hannover”
With https://pelias.github.io/compare it is found:
https://pelias.github.io/compare/#/v1/search%3Ftext=carl-neuberg-straße%20hannover