何か, なにか, なんか
Adverb
1. something, some, any
2. somehow, for some reason
3. (is there) something (you want, etc.)
ここまでのところで何か落としていることはありませんか。
を
Particle
1. indicates direct object of action
2. indicates subject of causative expression
3. indicates an area traversed
4. indicates time (period) over which action takes place
5. indicates point of departure or separation of action