On the Query Categories page, none of the query categories have the expand icon (+) next to the name. The category has to be clicked on directly and opened in order to view the queries inside:
Additionally, when searching for a query by name using the Find search box, the search only returns query categories that match the searched phrase, instead of returning individual queries that match.
The expand icon disappears once you have more than 1500 queries stored across all query categories. In order to restore the expand feature (and the Find functionality), queries will need to be deleted until the number of saved queries is under 1500. For steps on how to delete queries, click Can I delete queries and reports?
The expand icon can also disappear from the Communications or Reports section of the database, due to the same limitation on the number of items that can be stored in either section. For example, if there are more than 1500 reports saved, on the Report Categories page the expand icon will no longer be available.