Although the rules state that a golfer has five minutes to search for a lost ball one should never take this much time if not playing in a serious tournament situation. If one person from every group on the course did so during their time on the course, this would translate into approximately 3hrs of ball searching that players behind would have to endure.
Upon hitting the ball into a questionable location, first take note of its area as best you can from your current location. Then take a maximum of two minutes to search for that ball after arriving in the general location of where you think it may be. If the ball cannot be found in within two minutes, drop a new ball at the nearest point free of obstructions to where you believe the ball to be and play from there.
If all golfers played their lost balls as described above everyone's game would be faster and more enjoyable.