In Turkish, instead of I-i character in English we have two different letters, İ-i, I-ı. And not like in English lowercase i does not correspond to uppercase I, both have their own uppercase and lowercase versions as you can see above.

So lets say i have a name ismail, when i write it in uppercase its written as İsmail.

During searching for people (or email etc) lets say there is a person called İsmail, of course his name is recorded into database as Ismail since we are in a international company. In a computer reigon is set as Turkey, When you start searching lowercase i it does not look for a case match and search the database with lowercase i and uppercase İ not with I like it does in other regions. So it cannot find any result. You have to start with uppercase I or lowercase ı to find his name. But since in this name in Turkish is never written with these two characters, it prevents people to find their contacts or emails if they dont know this behavior.

The same issue can be found almost anywhere in Office Applications (like excel word etc if you are searching for a text in a document)

The search functionality has to be improved like below,

For in each line, all of the charaters below can be found instead of the others

I-ı, İ-i
U-u, Ü-ü
O-o, Ö-ö
C-c, Ç-ç
S-s, Ş-ş
G-g, Ğ-ğ