Sqlite3 - can't use characters with diacritics

I'm creating a method which takes a name as an argument and returns a row from Sqlite3 database. When trying to use non-diacritic characters, it works.

But if I try to pass a string which contains diacritic characters, it raises:

UnicodeEncodeError: 'ascii' codec can't encode character u'\xe9' in position 4: ordinal not in range(128)

When I try to print the same name to the console, it works.

 # -*- coding: utf-8 -*-
import sqlite3

conn = sqlite3.connect('data.db')
cur = conn.cursor()

def get_subject_by_name(name): # TODO: APROXIMATE SEARCH
    result = cur.execute("""SELECT nazov,ICO,pravna_forma,sidlo,predmet_cinnosti,den_zapisu,url_orsr FROM companies WHERE nazov LIKE ?""",('{}%'.format(name),)).fetchall()
    print result

get_subject_by_name(u"systém")

do you know where the problem could be?