Search engines know what city you live in, what tickets you are interested in and from what device you are looking for them. On the same flight, a New Yorker will see a higher price tag than an Indian from Delhi. And if you enter the same search query twice in the aggregator, you will see how the price rises with each query. Thus, the aggregator will not be able to find out if you have searched for such tickets before. If the site shows prices in pesos, then the money can be converted several times when paying. For example, if we talk about tourists from Russia, then it is most profitable to fly from Moscow, since it is a huge interchange hub, and besides, all major airlines fly through it. If you book a ticket in advance, then for 10 euros you can fly from Helsinki to anywhere in Europe. Ticket aggregators often ignore these tickets because they have low fees and look more profitable than regular tickets with high fees. You need to search for tickets yourself on the websites of airlines or on special resources. When buying a ticket for a low-cost airline, you should carefully read the airline's rules.