I think the usefullness of the search function depends on your choice of search terms, like any engine. The plus signs took a little getting used to, but I prefer it to other engines in some ways. As far as I understand it, the plus makes a word required in a post result, meaning if you have multiple words without plusses, it will give you all posts with either of those words, not both. With that in mind I'm usually able to find anything I'm looking for.