Why does searching on Stack Overflow and other communities not have spelling correction? Something similar to Google's spelling correction...
It does have some kind of spelling correction. Searching for 'spellings' and sorting on newest gives your question as one of the top results, even though it does not contain the word 'spellings':
This is the result of using so-called stemmers in Elasticsearch, the repository powering the Stack Exchange search.
If you frequently misspell words, it's better to install a browser extension which underlines wrongly spelled words in editable fields, and offers a context menu to correct them.