どうしても
No matter what, at all costs; (negative) just can'tmachine translation
Formationどうしても + verb (affirmative: strong desire; negative: 〜ない)
どうしても has two faces depending on whether what follows is affirmative or negative. With an AFFIRMATIVE clause, it expresses uncompromising determination or need: どうしてもその大学に入りたい (I want to get into that university no matter what), どうしても休めない会議 (a meeting I can't miss no matter what).
With a NEGATIVE clause, the meaning flips to "I've tried everything and still can't…": この漢字の読み方がどうしても思い出せない (no matter what I do, I can't recall how to read this kanji). Lurking behind it is always the image of having tried again and again.
The origin of the word is exactly that: どうしても = "no matter how it's done," so the two meanings are really one — whatever the method, the outcome doesn't change. Compared with とても〜ない — a pattern that only goes with negatives and means "beyond one's power, simply can't" — どうしても is broader, because it also works in the affirmative direction of determination.
Examples
どうしてもその大学に入りたいです。
I want to get into that university no matter what.
この漢字の読み方がどうしても思い出せません。
No matter what I do, I can't remember how to read this kanji.
明日はどうしても休めない会議があります。
Tomorrow I have a meeting that I absolutely cannot miss.