Having trouble searching with the * and @ symbols...

My question takes a little explanation … sorry for the length…

As a historian, I’ve been creating notes in DT. By my system, an
abbreviated citation for the source goes into the “Name” field, while
a label (basically an abbreviated summary consisting of a few words)
goes into the Comment field. I use essentially two categories of notes
– chronological notes and subject notes.

For each chronological note, I create the label (in the Comment field)
by beginning with an asterisk, then the date. For example:

*1921 08 21 John takes a trip

For each subject note, I begin with an @, followed by a standard
subject, followed by a year and a brief summary. For example:

@hobbies/1924/John's favorite hobby was sailing

Now, here’s my problem. I’ve been planning to sort my notes into Smart
Groups for particular chronological periods, or particular subjects.

for example: all chronological notes for 1921

or: all subject notes about hobbies.

But when I construct a search using the * (asterisk), for
chronological notes, or the @ for subject notes, the search mechanism
appears not to recognize those symbols. For example, let’s say I ask
for all notes with labels in the Comment field beginning *1921
(meaning that I want ONLY those notes with Comment labels that include
the exact search term *1921 – and NOT Comment labels that include
“1921” WITHOUT the preceding asterisk. When I do that, “Search”
appears to ignore the asterisk, and simply returns all notes with
Comment labels including “1921.” The same thing happens with searches
using the @ sign.

Can anyone tell me what I should do differently?

There are two problems here.

DEVONthink searches words that contain alphanumeric characters. If you clip your post into a DEVONthink database and search for @hobbies, the word hobbies will be found and highlighted, but the @ symbol has been ignored.

The asterisk symbol is used as a Wildcard symbol in DEVONthink searches. If, for example, you search for the string hobb^ the results will include hobby and hobbies.

An approach such as replacing the @ symbol by z, so that the term @hobbies becomes zhobbies, would work in searches.

Dates may be a special problem. If the first comment in the Spotlight Comments field is the date written as YYYYMMDD, you can search Comments for that term, e.g., 19210821 and sort the results by the Comment field. If you have comments such as 19210821 John takes a trip and 19210915 Mary had lunch, they can be properly sorted by the date of the event if you search Comment by the term, 1921*. Searching for 1921* AND John would limit the results to those about John.

Is there a way to have Devonthink search for special characters. Usually special characters are searchable when we prefix them by some special character or insert them in quotes.
I just can’t understand why a powerful search engine like devonthink can’t allow the simplest special character search. I can’t even search for a parenthesis! This is expensive for the price.