Search doesn't work on remote server

I am using the simple built-in search function. This works fine on my local computer but when deployed to the web server the same searches return zero results.

What might be causing this?

Is the correct controller/template called? Maybe wrong character set?

Edit: have you tried to var_dump the resulting search parameter?

Strange, this morning it started working without any change from me. Does it search live or is it based off a Sqlite db?

No, no database involved in search.