League of Legends (LoL) Question: How direct micro rockets!?

The rockets goes depending on where your cursor is in relation to Heimerdinger. For example, if you use your rockets whilst your cursor is on Heimer, your rockets will go in all directions. If you use your rockets and your cursor is further away from heimer, they will instead become more centered towards a specific location (where your cursor is) when firing.

You don't exactly direct them, the distance of your cursor in relation to Heimer is what define their angle (closer or further from him)

Hold click, don't just click. If that doesn't work then maybe it's a problem from your settings. If it is that, then turn ''Quick abilities'' off.

Are we talking about Heimer's W?