Full text search

[Korb]

Is your feature request related to a problem? Please describe.
I did not find any mention of the presence of full-text search of messages in the application in README.md. If it is implemented in the application, I suggest adding it to the list of functions supported by the application. At the same time, clarifying whether it supports regular expressions, fuzzy-, and morphology (indicating the supported languages).

If it is missing completely or partially, I suggest discussing the possibility of adding it.

Describe the solution you'd like
Editing of README.md (in case the search is present).

Describe alternatives you've considered
Use sorting, filtering by supposed echomail conferences, dates and senders. Search by enumeration of all probable messages.

Additional context
N/A