If your grasp of core material falls short of deep conceptual understanding, you will not be sure what is being asked or which conceptual tool should be used to solve the problem. Are the connections between concepts missing?
Told to hammer, they could hammer. Told to put in a screw, they could use a screwdriver. But told to build a shelf, they’d be paralyzed even though it was just a combination of concepts that they should have learned.- Salman Khan
Fixing gaps and lapses: Go back and revisit your study material. Read different books on the same topic. You will see the explanations from different angles and the material will make more sense. Work on actively applying the concept in a new context.
Reference
The One World Schoolhouse by Salman Khan