If you want a cheap flight from La Paz Bolivia to São Paulo, you've got zero airlines to choose from.
São Paulo Aeroporto Internacional Guarulhos Airport is just one of the airports in São Paulo. If you're not set on a specific airport, try changing your search from São Paulo Aeroporto Internacional Guarulhos Airport to São Paulo to see a broader range of flights – they might be cheaper.
During this peak season, hotel and holiday prices often increase too, so it's best to book early. Or you could keep your fingers crossed and hold out for a last-minute deal.