Buscar (Spanish for “to ask for”) comes from the Latin poscere (“to ask urgently”). In the transition from Latin to Spanish, the word was definitely weakened since buscar doesn’t have any urgent implication.
From this Latin root, we also get the English word… postulate. Postulating is really just formulating a thesis and wanting responses — which is just a sophisticated form of asking a question!
We can see the b‑s-c of buscar maps to the p‑s-t of postulate.