"Does Not Include" option for searches

Can you please include a "Does Not Include" option for searches. As it currently stands, not only must we battle through the crap to find the item we are searching for... but we will often just abandon the search all together due to irrelevant or blatantly misleading results. It would be so amazingly wonderful if we could search for a certain car, in a given price range & not have to search through hundres or thousands of posts which are not CARS but only a wheel nut or wrecking. Likewise, while searching for Employment or services, the abilty to exclude certain words with a simple -thisword or "not:thisword" would give your customers a greater advantage than other providers except uncle Google.