Search box can't do negative searches for tags?

The EagleFiler manual says that the search box can be used to find not only the contents of the records, but also their tags.

The manual gives an “apple -orange” example to demonstrate negative criteria. This example works when searching record content, but not when searching tags.

(I created two text records, one tagged “apple orange” and one tagged “apple banana”. Searching for “apple” finds both records. Searching for “apple -orange” finds no records.)

Are negative searches not enabled for tag searches?

Quoting the manual:

There are two kinds of indexed searches… There are also five kinds of exact searches…

The enhanced query syntax applies only to the indexed searches (Anywhere, Notes). The exact searches (including Tags) always try to match exactly what you type, so “apple -orange” means to search for records that have tag “apple” and tag “-orange”.

You can do negative searches for tags using smart folders.

Yes, I was using the Anywhere search. The manual implies that Anywhere searches tags in the same way as record content:

Anywhere
Searches the contents of the records, as well as the Title, From, To, Cc, attachment names, tags, and notes.

If this is not the case, then the manual should clarify this.

You’re right: the manual does not accurately describe what it’s doing. It should say something like this:

Searches the contents of the records, as well as the Title, From, To, Cc, attachment names, and notes. Also searches for records whose tags exactly match the query (ignoring the enhanced syntax below).

In more technical terms, it unions the results of an exact Tags search with the indexed search of the other areas.