Not sure what you are asking or what exactly you are having difficulties with. This is as basic as it gets, it will just require multiple layers/ emitters with slightly different settings to control the direction of the individual strands and the look of the particles. You can Do it easily even with Particle World or Particlke Systems II that come free with AE, though presumably having trapcode Particular would make some things a lot easier.
This would be quite easy to do if you have Trapcode Particular as Mylenium mentions. You can send out some particles that are invisible and use the Aux system to make the smokey trails. Then, just set your text layer as the obscuration layer and you're done!
Thanks Szalam and Mylenium I will use Trapcode Particular.