It is possible to choose the algorithm used to find suggestions for spelling errors, there are two algorithms on offer, 'hashing' (default) and 'phonetic'. Each algorithm has it's own advantages and disadvantages;
Hashing (default): Very fast, roughly 40 times faster than the phonetic algorithm, works best on typographic errors and common spelling mistakes. Similar to most spell checker suggestions.
Phonetic (Sounds like, English only): Slower, works well with genuine attempts to spell correctly, works poorly with typographic errors. Can appear to produce wild results, although results do sound like the word in question. Does not work with non English languages. Uncommon.
It is recommended that you choose the suggestions algorithm in line with your target audience. The phonetic algorithm, although appearing worse overall, is more suited for people who have not spoken English for very long, e.g. non native English speakers and children.