В поезде я всегда ищу место поудобнее у окна.

В поезде means in the train / on the train, referring to being physically inside it.

Russian often uses:

• в + Prepositional for being inside something
• на + Prepositional for being on a surface, or with some kinds of transport/location by convention

With поезд, the normal expression for being aboard is в поезде.

Examples:

• Я в поезде. = I’m on the train.
• Мы познакомились в поезде. = We met on the train.

By contrast, на поезде usually means by train, as a means of transport:

• Я поехал в Москву на поезде. = I went to Moscow by train.

So in your sentence, в поезде is correct because the speaker means while being on/in the train.

Поезде is the Prepositional singular form of поезд.

The preposition в takes the Prepositional case when it means in or inside a place:

• поезд → dictionary form
• в поезде → in the train

So:

• в поезде
• в доме
• в магазине

This is a very common pattern: в + Prepositional for location.

Yes. Ищу already tells you the subject is I, because it is the 1st person singular form of искать.

So grammatically, Russian could say:

• В поезде всегда ищу место поудобнее у окна.

However, Russian often includes pronouns when they sound natural, help structure the sentence, or give a little emphasis/clarity. Here я is completely normal and neutral.

So:

• ищу = I look for / I am looking for
• я ищу = I look for / I am looking for, with the pronoun stated explicitly

Because искать means to look for, while найти means to find.

In this sentence, the speaker is talking about a habitual action:

• I always look for...

That is exactly what искать expresses.

Also, искать is imperfective, which is the normal choice for:

• repeated actions
• habits
• ongoing processes

Since всегда means always, the imperfective verb fits perfectly:

• я всегда ищу = I always look for

If you used найти, the meaning would shift toward finding, not searching.

It is in the accusative, but for neuter inanimate nouns, the accusative singular is often the same as the nominative singular.

So:

• Nominative: место
• Accusative: место

Since ищу takes a direct object, место is accusative here, even though it looks unchanged.

Compare:

• Я вижу стол. = I see a table.
• Я ищу место. = I’m looking for a seat/place.

In both cases the object is accusative.

In this context, место most naturally means seat.

Literally, место is a broad word meaning:

• place
• spot
• space
• seat

But on a train, when someone says ищу место, they usually mean they are looking for a seat or a suitable place to sit.

So even though the literal word is place, the natural translation in context is often seat.

Поудобнее means something like:

• more comfortable
• a bit more comfortable
• somewhat more convenient
• a nicer/more comfortable one

It comes from удобный = comfortable / convenient.

The comparative is:

• удобнее = more comfortable / more convenient

With the prefix по-, it becomes:

• поудобнее

This often softens the comparison and gives the sense of a bit more or something nicer/better rather than a strong direct comparison.

So место поудобнее means:

• a more comfortable seat
• a seat that’s a bit better
• something more convenient

Both are comparative forms, but поудобнее is often a little softer and more conversational.

• удобнее = more comfortable / more convenient
• поудобнее = a bit more comfortable / somewhat more convenient / a nicer one

In many contexts, по- with a comparative suggests:

• a moderate improvement
• a less absolute comparison
• a natural conversational tone

So:

• Ищу место удобнее. = I’m looking for a more comfortable seat.
• Ищу место поудобнее. = I’m looking for a somewhat better / a bit more comfortable seat.

The second version sounds very natural here.

It is built from удобный.

Step by step:

• удобный = comfortable, convenient
• удобнее = more comfortable, more convenient
• поудобнее = a bit more comfortable / somewhat better

So the structure is:

по- + comparative form

This pattern is common in Russian:

• получше = a bit better
• побольше = a bit bigger / more
• поменьше = a bit smaller / less
• поинтереснее = a bit more interesting

У окна means by the window or near the window.

The preposition у takes the Genitive case, so:

• окно = window
• у окна = by the window / near the window

This is a very common expression:

• место у окна = a window seat
• сидеть у окна = to sit by the window

So окна is the Genitive singular form of окно.

All three can refer to being near the window, but у окна is the most natural and idiomatic choice here.

• у окна = by the window
• около окна = near the window
• возле окна = near the window / next to the window

In transport or seating contexts, Russian very often uses у окна:

• место у окна = seat by the window

It sounds simple, standard, and idiomatic.
Около окна and возле окна are understandable, but here they sound less natural than у окна.

Всегда means always.

It tells you that the action is habitual:

• я всегда ищу = I always look for

This is one reason the imperfective verb ищу is used. The sentence is not about one single occasion; it describes a regular preference or habit.

Russian word order is fairly flexible, though some orders sound more neutral than others.

The original sentence:

• В поезде я всегда ищу место поудобнее у окна.

This is very natural. It puts the setting first: On the train / When I’m on the train...

Other possible orders include:

• Я всегда ищу в поезде место поудобнее у окна.
• Я в поезде всегда ищу место поудобнее у окна.

These are grammatical, but the focus changes slightly.

The original version highlights the situation first:

• As for being on a train, I always look for a more comfortable seat by the window.

So the word order is flexible, but the original sounds natural and well-balanced.

Russian has no articles like a or the.

So место can mean:

• a seat
• the seat
• a place
• the place

The exact meaning comes from context.

In this sentence, English would usually say:

• I always look for a more comfortable seat by the window on the train.

The idea is indefinite, so a is natural in English, but Russian does not need any separate word for that.

Yes, you can think of it as one noun phrase centered on место.

Structure:

• место = seat/place
• поудобнее = more comfortable / a bit better
• у окна = by the window

So the whole phrase means:

• a more comfortable seat by the window

More literally:

• a seat, somewhat more comfortable, by the window

Both поудобнее and у окна describe место.

Yes. Поудобнее does not have to mean only physically soft or comfortable. In Russian, удобный can also mean convenient.

So место поудобнее у окна may suggest:

• a more comfortable seat
• a more convenient seat
• a better seat, from the speaker’s point of view

For example, maybe the speaker likes:

• the view
• somewhere to lean
• less disturbance from people passing
• easier sleep

So the phrase can carry both comfort and convenience.