Blood and Sand Gem explaining help needed!

hello guys i recently started playing Poe and now im having a skill called blood and sand and it says this:
Melee Skills have 5% less Area of Effect while in Blood Stance
Melee Skills deal (10-15)% more Area Damage while in Blood Stance
Melee Skills have (10-15)% more Area of Effect while in Sand Stance
Melee Skills deal 5% less Area Damage while in Sand Stance

am i correct in blood stance its single target damage
and in sand stance its aoe damage?

Partially correct. Sand stance lowers your AoE damage, not increase. Nevertheless, it makes your AoE skill have larger radius.

Melee skills that have no AoE tag such as Double Strike are not affected regardless if you are in blood or sand stance.

Molten Strike have AoE tag but the initial hit is not affected. Only the explosions from its magma balls are considered AoE and thus affected.