Go through your results for flights to Pullman in the USA with Netflights. Although KLM usually has the best prices, it's best to double check what's available for your travel dates.
Flexible on dates? Conducting your search by month allows you to compare prices to Pullman throughout the year. Accommodation prices will also be higher at this time of year.
But if you're struggling to find flights to Pullman that work for you, try looking at other airports in the USA.
Looking at a few different departure airports will give you even more choice. See what you can find. And remember, it's best to book your flights in advance wherever possible.