If you put things back where they belong, you won't lose them.
If you put things back where they're supposed to be, you won't have to look for them next time.
1) If you put things back where they belong, you won't lose them.
「物をあるべきところに戻せば、失くさないだろう。」
belong は「あるべきところにある・属する」
2) If you put things back where they're supposed to be, you won't have to look for them next time.
「物をあるべきところに戻せば、次（使うときに）探さなくても良い。」
look for で「〜を探す」
put things back で「物を戻す」
ご参考になれば幸いです！
日本 
