[Koha] non-Latin script display in Relevance

[tigran at flib.sci.am]

In Koha system (versions 3.08, 3.10, 3.12) for multi script records (e.g.
titles are in Latin, in Cyrillic, in Armenian)after search, when from
Relevance drop down menu selecting 'Title (A-Z)' the display for non-Latin
records is not in correct order. If for Latin records they are displayed
in correct alphabetical order, Armenian and Cyrillic records are mixed,
between the records with Armenian titles starting with the letter 'A' you
can see records for which the title is starting with the letters 'M', 'H',
then again 'A', then Cyrillic records are coming, and after those again
records with Armenian letters.
Any ideas?
thanks
Tigran