I wanna make mushroom and asparagus terrine ??any ideas how to make it

I found this recipe over at The New York Times. I don't see why you could steam some asparagus and layer it in.

http://www.nytimes.com/recipes/7212/Mushroom-Terrine.html

Alton' recipe calls for cheese which you might not want as it overpowers the taste of the asparagus and certainly the mushroom.
Sautée the mushrooms (more shrooms than you think) in order to remove their liquid.
Layer in the terrine, then blanched asparagus. I would add in some blanched carrot slices for color, repeat, the cover with your gelatine mix that you might flavor with some white vermouth or white wine (even sparkling).
Cover with plastic wrap and weigh down to gently compress while gelatine sets. Overnight will do it.
Slice with a warm knife.

Try googling it - I did asparagus terrine and this one popped to the top - looks like you use plain gelatine and I think you could build your flavors to suit your tastes:

http://www.foodnetwork.com/recipes/alton-brown/asparagus-terrine-recipe/index.html