Playing habits are changing.
From what I've seen, kids are jumping from toys to gaming consoles/tablets/cell phone games at a younger age these days which makes the toy buying period shorter than it used to be.
They'll ask for the occasional toy or gadget based on what they've seen on TV or in the movies, but it usually end up on the pile once there's a new fad in town.
Unlike Playmobil who has a steady schedule of releases throughout the year, many toy companies have distribution problems which either leaves the same toys on the shelves for months if the shelves are not simply left empty.
New assortments are easier to find online than in stores.
All that combined, it's no real surprise that even a giant like TRU would have difficulties. They might have to adapt to today's market. Maybe turn towards the toy collectors who are still a huge part of the market.