Krunner excludes possible results, when using greek locale, since it perceives 
vowel letters with accent mark as different than the ones without.

My suggestion is to accept the following equalities:

α U+03B1 = ά U+03AC = Α U+0391 = Ά U+0386 (Alpha)

ε U+03B5 = έ U+03AD = Ε U+0395 = Έ U+0388 (Epsilon)

η U+03B7 = ή U+03AE = Η U+0397 = Ή U+0389 (Eta)

ι U+03B9 = ί U+03AF = ϊ U+03CA = ΐ U+0390 = Ι U+0399 = Ί U+038A = Ϊ U+03AA (Iota)

ο U+03BF = ό U+03CC = Ο U+039F = Ό U+038C (Omicron)

υ U+03C5 = ύ U+03CD = ϋ U+03CB = ΰ U+03B0 = Υ U+03A5 = Ύ U+038E = Ϋ U+03AB (Upsilon)

ω U+03C9 = ώ U+03CE = Ω U+03A9 = Ώ U+038F (Omega)

Reproducible: Always

Actual Results:  
As a simple example if I wanted to pause the player I would type "παυση" (pause) but nothing would happen, so I need to strickly type "παύση" to get the disared result. (Just the first to letters wouldn't give any result.)

Expected Results:  
Thus searching for "παυση" (pause), krunner will offer to pause the audio player.

Basically in Modern Greek a vowel letter is combined with accent marks to mark the stressed syllable of polysyllabic words. 

When typing in the search prompt of krunner or anywhere else, it is common to forget putting accent marks due to being hurry and the extra keystrokes it requires.

Plus the stressed syllable may change, depending on different factors e.g. the case of the word, so you may need to guess the correct case of the world to get the desired result.

Also gnome search field already does that so I think it is possible.