First of all, check out the other posts on Common Magic and the like, to give your characters ideas about Common Magic spells that they could learn.
Second, they may actually prefer to solve their own problems instead of having a spell solve every little problem for them. This may actually work out better for the characters, if they don't particularly fancy lots of magic in their game; they could develop some heroic abilities instead of spells.
Unless you as Game Master actually throw magical challenges at them, they'll continue to do things non-magically. If a character has some sort of spirit warding spell like Spirit Bane, have them face spirits; if they have Push/Pull, have them face a puzzle that only Push/Pull can solve, such as the puzzle below.
The characters encounter a door, sealed shut, immobile and featureless except for an aperture in the wall on the left, slightly smaller than the size of a human head. An arm could fit through, but not a head. Beyond the aperture they see an empty space and a stone panel at the back, far out of reach. Only Push/Pull can move the panel, pulling it forwards towards the character, moving the piston connected to the panel and opening the door. The builder of this fiendish puzzle door had invented Push/Pull, and built this doorway specifically to ensure nobody would ever completely forget it. They would have to learn it to pass through the doorway; this knowledge would save their life, and ignorance would doom them to extinction.