To see a wider selection of flights to São Paulo, try searching by city rather than by airport.
If you don’t have specific dates for when you'd like to fly to São Paulo, try searching by month. It's also worth looking out for flights with American Airlines, as their fares are normally the best-value.
Accommodation is typically pricier at this time of year too. If you want to go at this time of year, try looking at other cities in Brazil to get a cheaper flight.
Whoever you want to fly with, it's best to book your flights in advance, particularly if you want to fly on a specific date – otherwise they may sell out. Once you've booked, why not take a look at accommodation? Simply click on the ‘Hotel’ tab at the top of the page.