Multi-Skill Skills

How do people make those skills that open up to others? Like, the build ability, or the learn skill ability, except you can use other skills. That sounds confusing, so here's an example:

My hero's skill card has a skill in called "Water Abilities". When you click it the card changes to show 9 skills related to water. There's also the back icon in the 12th slot.

Any ideas? I was thinking that it had something to do with selecting a new hero, but there must be a simpler way.

There is a ability called spellbook. In that you can add new ablities. When a hero gets the spellbook he can click on it, then show all the spells of the spellbook.

Thanks, I'll look into it.