"This is not sold in Japan."
「これは日本では売られていない」
"This is my favorite chocolate but it's not sold in Japan."
「私の大好きなチョコレートだけど日本では売られていない」
"My friend got me this from the Philippines because you can't buy this in Japan."
「これは日本で買えないから、友達がフィリピンで買ってきてくれたの」
ご参考になれば幸いです。
This is how you can explain it to your child. Even though Japan imports or buys many products from other countries, it is impossible for every country to have the same products. Every country is special because of the products that we have.
"This product is not sold in Japan!"
"We don't have this product in Japan!"
これは子どもに伝える言い方です。日本はいろいろな製品を海外から輸入していますが、全ての国が全く同じ製品を持つということはあり得ません。そこにある製品は国によって異なります。
"This product is not sold in Japan!"（この製品は日本では売られていません）
"We don't have this product in Japan!"（この製品は日本にはありません）
"We cannot get this item in Japan!"
Cannot - something you are not able to do.
Get - you cannot buy it in a store or order it online.
Item - food, candy, toy, drink, etc. This word refers to any object.
You can change the sentence to say, "We cannot get this candy in Japan." or "We cannot get this soda in Japan."
"We have to travel abraod to get this item."
Travel abroad - you have to visit another coutnry to purchase the item.
"We cannot get this item in Japan!"（この商品は日本では手に入らない）
Cannot - できないこと
Get - お店やインターネットで買えない
Item - 食べ物、お菓子、おもちゃ、飲み物など。この単語はあらゆる物を指します。
次のように言うこともできます。
"We cannot get this candy in Japan."（このお菓子は日本では手に入らない）
"We cannot get this soda in Japan."（このソーダは日本では手に入らない）
"We have to travel abraod to get this item."（海外に行かないとこの商品を手に入れることはできない）
Travel abroad - 他の国に行かないとその商品は買えないということ。
"This isn't available in Japan"
to be available means that you are able to access something ex. food, drink, movies etc.
"This ATM is currently unavailable"
"You can't get this in japan" Is a casual expression and can be used in different contexts ex. "You can't go through this door".
"This isn't available in Japan"（これは日本では手に入りません）
= 'available' は「（食べ物・飲み物・映画などが）利用できる」という意味です。
例：
"This ATM is currently unavailable"（このATMは現在利用できません）
"You can't get this in japan"（これは日本では手に入りません）
= これはカジュアルな表現で、いろいろ文脈で使うことができます。
例：
"You can't go through this door"（このドアは通れません）
When you want to explain to a person/child that you cannot buy something in Japan; then you may explain this in the following ways:
-This is not sold in Japan.
-You will not find that in any store in Japan
それは日本では買えない商品だと（子どもに）説明したいなら、次のように言えます。
-This is not sold in Japan.（これは日本では売られていません）
-You will not find that in any store in Japan（それは日本の店では売られていません）
Not all countries sell the same things as they make or import different things if something is not able to be bought then you can say it is 'not sold', 'not available' or you 'can't buy' it
"You can't get this in Japan" is a very straightforward way to state something cannot be attained in Japan.
"They don't sell this in Japan" clearly refers to the purchase and sale of an item that cannot be completed in Japan.
"This isn't available in Japan" as above, is another way to state that an item, product or service even, cannot be offered in Japan.
"You can't get this in Japan"
（これは日本では手に入らない。）
これは、日本であるものが手に入らないことを伝えるストレートな表現です。
"They don't sell this in Japan"
（これは日本では売っていない。）
これは日本ではそれを買うことをができないことを伝えるフレーズです。
"This isn't available in Japan"
（これは日本では買えない。）
これは、上の例のようにそれが日本で買うことができないという意味です。
The shops in Japan don't have Marmite (for example)
You want to say to a child that a certain food is not sold in Japan. You could try one of the above suggestions. If the child is a little older, of course, you could use the word 'available' which is a better explanation.
Eg 'Marmite is not available in Japan.'
You can't get that in Japan.
It is not sold in Japan.
We don't have that here.
When you want to explain to someone that a product or item is not available in Japan, then you can use one of these three sentences.
I hope that helps.
Have a great day.
Will
When a certain food is not sold in a country it can be due to a number of factors, for example: the food is not grown or produced there due to the climate, the food isn't brought into the country due to the cost of importing it from another country, supply and demand is also another factor in this situation.
日本 
南アフリカ 
アメリカ合衆国 
イギリス 
オーストラリア 
ニュージーランド 
