AND and OR
In your where statement, you can combine multiple conditions. Here we show "big" countries that have a large population (greater than 40 millions), OR a large area (greater than 2 million square km)
Modify the query to find tiny crowded countries, with less the 1000 square km of surface AND more than 1 million inhabitants.
SELECT name, population, area FROM world WHERE population>1000000 AND area <1000