Literature Reference: 沙含水弩多伤骨，田仰畬刀少用牛。——《酬乐天得微之诗知通州事因成四首 一》 The sand conceals water crossbows that harm bones, while fields rely on fire-clearing tools, sparing oxen. Source from 'Four Poems in Response to Letian's News of Tongzhou Affairs'.
沙: Sand, grains of sand.
含: Implication, encompassing.
Meaning: Sand and water symbolize resilience and hidden strength, representing inner power and wisdom.