Yes, that's a consequence of our typo-tolerance handling. We're computing a damerau-levenshtein edit-distance and are currently allowing 2 typos if the word is at least composed by 7 chars. Regarding the corpus, we'll probably increase it to 8 or 9 (instead of 7 by default) to allow 2 typos and 4 (instead of 3 by default) to allow 1 typo.