looking for something; searching for something
Refers to the act of searching for a lost or desired item. Often used in contexts like 探し物をする or 探し物が見つかる.
朝からずっと探し物をしている。
I've been looking for something since this morning.
object being sought; lost item
Refers to the thing one is looking for. Common in phrases like 探し物はこれですか?
探し物は見つかりましたか?
Did you find what you were looking for?
I'm looking for something in my room.
Is this the thing you were looking for?
I finally found what I was looking for.
Alternate kanji spelling using 捜 (search), equally common.