I'm not sure what you mean by "trying a string", that's not something that seems to me to be something related to suggesting a site.
The process works something like this:
1/ A member of the public find a site that they think might add value to the directory.
2/ They use the web form we provide to suggest the site to an appropriate category. (Right now we're having some technical problems, so you can't actually do this stage at the moment -- Watch the announcements here for more news.)
3/ A volunteer editor reviews the suggested site, and decides whether it should be included.
4/ If appropriate the site is listed, and will then be on public view as part of the directory.
More details about the suggesting part can be found at
http://dmoz.org/add.html
More details about how we decide which sites to list can be found at:
http://dmoz.org/guidelines/include.html
The FAQ here also provides useful information, including explaining that since all our editors are volunteers, we can't provide any time scale for the review process:
http://www.resource-zone.com/forum/faq.php?faq=odp#faq_faq_site_questions
(Finally, please don't suggest a site multiple times -- it only adds to the work of the editors, and may slow down the review process even more. It's also contrary to the submission policy that you need to agree to when you submit the form.)