With some souvenirs such as painted tin boxes, such items as sweets or biscuits cannot be seen as the lid of the tin is usually sealed. One of the above phrases would be sufficient for this request.
"How many pieces/items are included/inside."
This asks them to tell you how many pieces are in the box.
"Pieces and Items" means the same.
"Included and Inside" means the same.
"How many pieces/items are included/inside."
これはその箱に何個入っているのかを聞いています。
"Pieces and Items" も"Included and Inside"も同じです。
Do you have different box sizes with different quantities inside a box?
How many chocolates are inside each box?
Quantity - The amount of an item.
All of the above are clear and can be used in this situation.
1.What is the quantity per box? - direct question asking how many items per box.
2.Do you have different box sizes with different quantities inside a box? - Asking if they have different amounts in boxes. Example - 50 per box, 100 per box, 200 per box... etc.
3.How many chocolates are inside each box? - Asking directly how many chocolates in the box.
Quantity - 物の数
上の全ての表現は明らかでこの状況で使えます。
1.What is the quantity per box? - 箱ごとにいくつ入っているか尋ねる直接的な表現です
2.Do you have different box sizes with different quantities inside a box? - 彼らが箱に違う量が入ったものも扱っているか聞いています。
Example - 50 per box, 100 per box, 200 per box... etc.箱に５０個入り、１００個入り、２００個入り・・・
3.How many chocolates are inside each box? - 箱にチョコレートがいくつ入っているかを直接的に尋ねている
We can ask how many there are, "per box," which might be useful if we are considering buying multiple. We can use, "inside each box," or simply with just the word, "inside," to mean the same thing.
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