Bolero is one of the ancestors of Bachata. (The other two: Son and Merengue).
Bachata music usually has three "levels" of "energy":
-Derecho: Lowest "level", and the may remind one of Bolero.
-Majao (J is pronounced like an H): Medium. More emphasis on the percussion.
-Mambo: The most energetic one: Feels more Merengue-ish. A good indication it is the mambo section would be the guira, playing more rapidly.
Here are some Bachatas: Compare them to the Bolero you've posted. (and while at it: play a game of guessing when the music switched "levels").