1. A computer-implemented method for adjusting search areas, the method comprising the following operations performed by at least one processor: determining a route distance based on information for a route; comparing the route distance with a distance threshold; defining a search area when the route distance is less than the distance threshold, the search area including boundaries; calculating a points of interest (POI) density of the search area; determining if the POI density is greater than a first density threshold and less than a second density threshold; increasing the boundaries of the search area when it is determined that the POI density is less than the first density threshold; and decreasing the boundaries of the search area when it is determined that the POI density is greater than the second density threshold.