When you find no words

I got a box full of courage
But I don´t remember where I putted the key
I tried to tell don´t insist with that
But it looks like I said it in my own language

I lost many sadnesses, but you come back with that old one
I thought it wouldn´t come to stalk me again
Now I lost the key for my box
Search for it won´t be enough
That´s why I say goodbye