I just noticed this morning that CanLII has introduced a help feature. When you mouse into any of the search entry fields, a popup appears with the various options available to you to do a Boolean search dans les deux langues, naturellement. The graphic below shows what comes up when you mouse over the “full text” entry field.
It’s possible that this has been around for a while and I’m the last to find it — if so, I apologize for the stale news. But CanLII has a habit of introducing changes by stealth, so it might indeed be brand new. Whichever is the case, it’s really helpful.