Please note at the time this article was published, two-letter search for Apps is not possible by design. This may change in future.
When creating or editing Application Settings for DNS or Web policies, it is not possible to search directly for applications with less than three letters in their name. For example, it is not possible to search for the two letter application names "QQ" or "YY".
As a workaround, these apps must be manually picked up from the tree under their respective categories or else wild-carded in a search, for example by searching for "QQ*" or "YY*".
This is an intended behavior and by design.