Funnel is any structure (pond,fence,saddle in ridgetop, river, blowdown, edge cover,,,ect) that forces deer to "funnel" their movements.
My key is to find the bedding areas as well as the food source at the correct time of year. Food source could be crops, mast or a weedy browse patch. Deer leave ragged riped edges when they browse, rabbits, ect. leave clean crisp cuts.
Get out this time of year and find where the bedroom is. Crawl if you have too through the thickest cover on your property that people never go into. You will find deer sign. I like to pick a rainy day so I don't make much noise.
Experience is a great teacher. Call your state deer biologist if need be. They are a great information source regarding food sources. Remember if this was easy it wouldn't be any fun.
John II