With $20 budget and 4 versions this seems like a random spike in data. If you are going to use this method I suggest to use Google AdWords Campaign Experiments (built-in tool). It will tell you if your results are statistically significant. There is also Excel spreadsheet to download and play with numbers to see if results are significant.

Second caution. This approach only tests what's the best name for your ad. It doesn't tell you what is the best name for your product.