se los dije

I told them

→ se
phrase Rare #44,925
I told them Here, “se” means “to them,” and “los” refers to what was told. The specific thing may be understood from context.
SP: Se los dije ayer, pero no me escucharon.
EN: I told them yesterday, but they didn’t listen to me.

Aprendí mucho de ellos y se los dije.

I learned a lot from them, and I told them so.

Se los dije, no?

I told you guys, didn’t I?

— Juego sangriento [バトル・ロワイアル] (2000)

¡Yo no se los dije!

I didn’t tell them!

— Museo (2018)

Lo de Santa Claus no existe no se los dije.

I didn’t tell them that Santa Claus isn’t real.

— Museo (2018)

Se los dije.

I told you so.

Ya se los dije.

I already told you.