Preserving THC while mailing

Okay i recently got a shipment of some dro..idk what strain but i plan on receiving more stuff in the near future..i was wondering is there a way to perserve the THC when its vaccumed sealed?? would putting it in a ziplock bag then putting that bag in a vaccum seal bag help or what?? and how do you get the bud to get back to being fluffy again..