Search wins are random. Others might win off something you searched just because it is time for them to win not because of that phrase. You can win up to 4 times a day with searches. Often your first search of the day is a winner and the others are usually about 4 hours later.
A few years ago there was a 'conspiracy theory' going around that there were magic keywords that provided big wins. This was quickly dispelled though. I've won 100 SB for searches twice in the past 7 years but they were random and no one else won that amount off of those phrases I used.