Unfortunately, simply submitting your pages is only part of the job. With millions of pages in dozens of search indexes, the odds of many people finding you are still not very good without careful planning. Even after you submit, the page can often be dropped later for no apparent reason or never be accepted at all. Search engines are not yet 100% accurate. But considering the sheer volume they deal with everyday, its understandable, but unfortunate that there will be random errors. The main reason submitting is not enough are your positions. It takes some follow up, revision, and resubmitting of your pages to improve your positions on the search engines. If people search for a keyword or phrase and can't find you, then you might as well not be in the search engine index at all!