Not sure I understand. Just in general what might sound good? If we assume the C# in the A chord is an accidental and we are in the key of D minor, then you could play F (or Fmaj7) or G (or G7). C would be a cool choice as well as depending on how you voice the chords you would have a descending chromatic line from D, to C#, to C. Apply a partial Circle of Fifths concept and you could have a nice little progression of Dm, A (play Amin or even Amin7 to be fully in key), C, G7.

E major

Wait, so what's the progression? F min and A present a rather interesting progression as they don't share a key signature. Not that there's anything wrong with that as what's important is whether or not things sound good to you. A few chords which would line up diatonically with F minor: Bb7, Cmin7, and Ab.

I apologize if I'm throwing around some advanced terms, I'm not a good teacher. Chord theory is one of those things which makes guitar such a fun and unique instrument.