This isn't really the way that this site works. People don't just send you the source code. There's a very good reason why this is the case - the code that you get sent will probably not be solving exactly the issue that you are trying to solve. Search functionality can be very specific to a website because it can depend heavily on queries on particular fields and the technology underlying the database. Suppose, for instance, that you want to search for people's names and account ids, having a search that searched through article fields would be completely irrelevant.
If you want to opt for a more free form of text searching, you really need to investigate full text search systems such as
Sphinx[
^].