Tôi lo về bưu kiện.

Tôi means I and is a common, neutral, fairly polite way to refer to yourself.

It is not the only way to say I in Vietnamese. Vietnamese pronouns depend a lot on age, social relationship, and context. For example, people may say mình, em, anh, chị, etc., depending on who they are talking to.

For learners, tôi is a safe default in many situations, especially in textbooks and formal speech.

Here, lo means to worry or to be worried.

So Tôi lo means I am worried.

A useful thing to know is that lo can have other meanings in other contexts, such as:

• to take care of
• to arrange
• to provide for

For example:

• Tôi lo cho gia đình. = I take care of my family / I worry about my family.

In Tôi lo về bưu kiện, the meaning is clearly I’m worried about the package.

In this sentence, về means about or regarding.

So:

• lo về + something = to worry about something

That makes Tôi lo về bưu kiện literally something like:

• I worry about the package

Vietnamese often uses short words like về to show the relationship between ideas. Here it links the feeling lo with the topic bưu kiện.

Usually, no—not if you want this exact meaning.

Tôi lo về bưu kiện sounds complete and natural.
But Tôi lo bưu kiện sounds incomplete or unnatural in standard Vietnamese.

If you want to say worry about, you normally need something like về or another structure such as lo cho in some contexts.

Compare:

• Tôi lo về bưu kiện. = I’m worried about the package.
• Tôi lo cho bưu kiện. = possible, but this can feel more like I’m concerned for the package or even I’m taking care of matters related to the package, depending on context.

Bưu kiện means parcel, package, or postal package.

It is a fairly specific and somewhat formal word, often used for something being shipped or delivered.

A more everyday word you may also hear is:

• gói hàng = package / parcel / shipment

So:

• bưu kiện often sounds a bit more like postal parcel
• gói hàng often sounds more everyday and conversational

Because Vietnamese does not need a word like am here.

In English, you say:

• I am worried

In Vietnamese, a state or quality can often come directly after the subject:

• Tôi lo = I am worried

So lo already works naturally as the main predicate. You do not need là here.

A common learner mistake is trying to say:

• Tôi là lo
  This is incorrect.

It can mean either one, depending on context.

Vietnamese does not use articles like a, an, and the the same way English does. So bưu kiện by itself is just package/parcel, and the exact meaning comes from the situation.

If you want to be more specific, you can add words such as:

• một bưu kiện = a package
• bưu kiện này = this package
• bưu kiện đó = that package

Yes, it is understandable and natural enough.

That said, depending on the situation, native speakers might also say:

• Tôi đang lo về bưu kiện. = I’m worrying about the package right now.
• Tôi lo lắng về bưu kiện. = I’m worried about the package.
  This sounds a bit fuller or stronger than just lo.
• Tôi lo về gói hàng. = same basic idea, with a more everyday word for package

So your sentence is fine, but there are a few common alternatives.

Yes, fairly similar.

The structure is:

• Tôi = I
• lo = worry / am worried
• về = about
• bưu kiện = package

So the pattern is basically:

subject + worry + about + thing

That makes this sentence quite easy for English speakers to follow.

The main difference is that Vietnamese does not need a separate word for am.

A rough pronunciation guide is:

• Tôi ≈ toy
• lo ≈ law
• về ≈ vèh with a falling tone
• bưu kiện ≈ roughly byoo kee-uhn, though the second syllable is shorter and heavier than in English

The tones are:

• tôi — level tone
• lo — level tone
• về — falling tone
• bưu — level tone
• kiện — heavy/glottalized tone

If you want to sound natural, the tones matter a lot more than the English-style approximation.

Sometimes, yes—if the subject is already clear from context.

In conversation, Vietnamese often drops subjects when they are understood. So if everyone knows you are talking about yourself, you might just say:

• Lo về bưu kiện quá.

But as a full, clear sentence, especially for learners, keeping tôi is best:

• Tôi lo về bưu kiện.