Đây là bưu kiện quốc tế.

In this sentence, đây means this or here.

The pattern Đây là ... is very common in Vietnamese for identifying or presenting something:

• Đây là bưu kiện quốc tế. = This is an international package.
• It can also feel like Here is the international package, depending on context.

So đây is the word that points to the thing being shown.

Là is the linking word here, similar to is in English.

In Đây là bưu kiện quốc tế, it connects:

• đây = this
• bưu kiện quốc tế = international package

So the structure is basically:

• Đây
  • là
    • noun phrase
• This
  • is
    • noun phrase

A useful contrast:

• With a noun, Vietnamese often uses là: Đây là bưu kiện quốc tế.
• With an adjective, Vietnamese often does not use là: Bưu kiện này nặng. = This package is heavy.

Vietnamese does not use articles the same way English does. There is no mandatory equivalent of a/an/the in a sentence like this.

So bưu kiện quốc tế can mean:

• an international package
• or, depending on context, the international package

If you want to make a/one more explicit, you can add một:

• Đây là một bưu kiện quốc tế.

That is also correct. Without một, the sentence is still completely natural.

Bưu kiện means parcel or package, especially in a postal or shipping sense.

It sounds a bit more official or postal-service-like than some everyday alternatives.

For example:

• bưu kiện = parcel/package, often in mailing or delivery contexts
• gói hàng = package/package of goods, often more everyday
• kiện hàng = shipment item, cargo package, sometimes larger or more commercial

So in a post office, shipping, or customs context, bưu kiện is a very natural choice.

Because Vietnamese usually puts many modifiers after the noun, not before it like English often does.

So:

• bưu kiện quốc tế
• literally something like package international
• natural English: international package

This word order is very common in Vietnamese. Other examples:

• chuyến bay quốc tế = international flight
• sinh viên Việt Nam = Vietnamese student
• công ty lớn = big company

So the noun comes first, and the descriptive part often follows.

Yes, it is functioning like an adjective in this sentence.

In bưu kiện quốc tế, quốc tế describes what kind of package it is: an international one.

Vietnamese does not change adjectives for singular/plural, gender, or anything like that. So quốc tế stays the same no matter what noun it describes.

This is a very common question.

• đây can stand on its own and often means this or here
• này usually comes after a noun and means this

Compare:

• Đây là bưu kiện quốc tế. = This is an international package.
• Bưu kiện này = this package

So you can think of them like this:

• đây = standalone pointing word
• này = noun-attached this

That is why the sentence uses đây, not just này by itself.

Yes, it is correct and natural, especially in a shipping, postal, customs, or logistics context.

It may sound slightly more formal or official than everyday casual speech because bưu kiện is a fairly standard postal term.

In casual conversation, someone might also say:

• Đây là gói hàng quốc tế.

But Đây là bưu kiện quốc tế is absolutely normal and appropriate.

A rough guide for an English speaker is:

• đây → roughly like day
• là → roughly lah with a falling tone
• bưu → roughly byoo
• kiện → roughly kee-uhn, but said as one syllable
• quốc → roughly gwok or wok, ending with a clipped k
• tế → roughly tay with a rising tone

A few helpful notes:

• đ is like a regular English d, not like English th
• Vietnamese tones matter, so copying native audio is very helpful
• quốc ends sharply; do not fully release the final k like in English

So the whole sentence is approximately:

day lah byoo kee-uhn gwok tay

That is only an approximation, but it is a useful starting point.