first of all...getting searched, and getting your bag searched...is two different instances. it isnt a federal check, so if you were able to capitalize on this moment of freedom and take something out of your pocket and put it in your bag, or put it in your bag from your pocket....depending on your slickness, youre good to go. the bags go under the truck.
i dont ride greyhound anymore but i used to sneak weed and bottles of liquor all the time...id usually hustle off all the weed before i get to where i have to go (EVERYONE on the bus needs weed...and i mean everyone..and you make alot of friends and meet alot of people on greyhounds if you stay social) and have to either save a bit or reup in the new town
if you feel parinoid, at the rest stop on greyhounds theres other buses headed to the same place on shorter routes to cities or specific layovers that are shorter like...instead of 40 min itll be 25 or something...and there might be open seats so you can just bounce off into a new bus somewhat undetected. you go about finding this out by asking the bus drivers (usually inside buying food or drinks, or the only one in or around the bus) greyhound is usually cool with exchanging buses, as long as youre getting to the same place.
in some situations id think you wanna tell the OTHER bus driver youre doing this too. its not that they wont leave you, which they WILL do, but its courtesy. i kinda get the feeling theyre more apt to flag you by not being there than if you let them know....
best bet though is to not bring too much, the higher up on your body the better as far as a dog, and try to visualize where youre patted down and find "blind spots" outside of those patterns
not too much info hope its helpful at all people fail when they get all nervous about the shit...if they catch you just say well fuck your greyhound trip, bounce with yo weed and take another bus company out to where your going lol