I believe search results are showing from this community only. I suggest having search results from magento.stackexchange.com ( I know this as another active Magento community ) also. If it is not a good idea, at least a search link with same query term (https://magento.stackexchange.com/search?q=layouts) somewhere in the search page to other Magento communities will make the job easier and visitors will be aware of other Magento communities as well.