how to search for hyphenated words? (was: how to search for Morse code?)

[Gregor Zattler]

Hello,
* Gregor Zattler <telegraph at gmx.net> [2018-07-23; 14:20]:
> today I searched for emails containing
>
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today I searched for emails containing "org-notmuch" (which
supports org links to notmuch searches), e.g. with

notmuch search org-notmuch
notmuch search -- org-notmuch
notmuch search -- "org-notmuch"
notmuch search -- '"org-notmuch"'
notmuch search -- '+"org-notmuch"'
notmuch search -- org ADJ/1 notmuch

all these resulted in very many hits most or all of which do not
contain the string "org-notmuch", one found email was e.g.

id:20180904105723.15564-3-david at tethera.net


How would one search for hyphenated words with notmuch?

Ciao; Gregor
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