Based on what wataniyob said, It's possible since the maintenance of the site, that the database is playing catch-up to display things.
For example, you submit your work to the site and it gets entered into the database (meaning you can see it as a submission), but it takes a day or so to make it appear in the browse/search features.
It's also possible that you are getting a cached response when searching for those tags, you could try clearing your cache to see if this avails it for you. (It may not work, but it's worth a try)
Here's a link on how to do it, if you're not sure: >>
Refresh your cache - When hitting F5 just isn't enough!