Finding the right content in a chat history can be quite time consuming and therefore I am looking for a functionality similar to Expression Search in Thunderbird Plugin.

Use-case:

I want to search for an email/chat with an attachment e.g. from mike which was sent in the last 30 days. I can imagine a similar scenario for a chat correspondence.

Syntax:

days:(0 -30) f:mike a:yes or ....

I think that the following commands can help to improve the search functionality a lot and to save time.

from:mike or f:mike
This expression searches all messages from 'mike'.

to:bill or t:bill
This expression searches all messages to 'bill'.

attachment:yes or a:yes
This expression searches all messages for an attachment

filename:foo.doc or fi:image or fn:msword or file:html
This expression searches all messages for an attachment name or type.

is:replied or i:UnRead
This expression searches all messages for status, The status can be one of Replied, Read, Marked, UnRead, New or Attachment.

ag:3 or da:3 or age:3 or older_than:3 or days:(3 -5) or age:today or newer_than:8week
This expression searches all messages to match age in days. days:(3 -5) will search for messages that age between 3 to 5 days.

body:electric bill
This expression searches all messages for 'electric bill' in the body of the message.

label:Important or tag:TODO or l:NA
could be used for hashtags

before:2011/03/09 07:12:00 or be:09 Mar 2011 05:00:00 or after:Mar 10, 2011 or af:(2011/03/01 -2011/03/09)
This expression searches all messages within the date range.

date:2011/01 or date:2011/01/03 or d:" 03:"
This expression searches all messages to match date. The internal format for compare is "yyyy/mm/dd hh:mm:ss", locale date is also supported.