without success
Y yo, para proteger mi matrimonio, intenté comprarla sin éxito, así que la maté.
And I, to protect my marriage, tried unsuccessfully to buy her off, so I killed her.
— Contratiempo (2017)
Sin éxito, yo intenté traducir esta oración en Toki Pona.
I tried unsuccessfully to translate this sentence into Toki Pona.
Estábamos intentando resolver el problema sin éxito desde hacía varias horas.
We had been trying to solve the problem unsuccessfully for several hours.
Unsuccessfully.
No sabes silbar pero lo intentas todo el tiempo sin éxito.
You don't know how to whistle, but you try all the time without success.