go around, conceal
邏 centers on circular or back-and-forth movement: going around, patrolling, or circling. The "conceal" sense is a less common application, likely from the idea of moving around something to hide or obscure it.
邏 combines 辶 (movement) with 羅, which likely contributes the sound and the idea of a net or spreading out, suggesting moving around in a net-like pattern. The exact historical development is uncertain.
The movement radical 辶 wraps around 羅, which looks like a net or a spread-out mesh. Picture a guard walking around a perimeter, weaving a net-like patrol path to go around and conceal any gaps.
For ラ, imagine a guard going around singing "la la la" as they patrol: la -> ラ, and the sound echoes as they circle the area.