Kad bi on imao više strpljenja, ne bi mu toliko smetale male pogreške.

In this sentence, kad bi introduces a hypothetical situation, so it is best understood as if rather than a literal when.

So:

• Kad bi on imao više strpljenja... = If he had more patience...

In Croatian, kad bi can be used for unreal or imagined conditions, especially in everyday language. A learner may also see:

• Ako bi... — also possible in some contexts, but less natural here
• Da ima više strpljenja... — another common way to express a hypothetical idea

So although kad normally means when, in a sentence like this it functions more like if.

Croatian commonly uses the conditional particle bi in both the if-clause and the result clause when talking about unreal or hypothetical situations.

Structure here:

• Kad bi on imao više strpljenja = If he had more patience
• ne bi mu toliko smetale male pogreške = small mistakes would not bother him so much

This differs from English, where we usually say:

• If he had...
• ...he would not be bothered...

So English uses a past form in the first clause and would in the second, but Croatian often uses conditional marking in both clauses.

Imao is the masculine singular active past participle of imati = to have.

It appears with bi to form the conditional:

• bi imao = would have

Because the subject is on = he, the participle is masculine singular:

• on bi imao
• if it were ona = she, it would be ona bi imala
• if it were oni = they, it would be oni bi imali

So imao agrees with the subject.

Yes, it could be omitted.

Croatian often leaves out subject pronouns when the meaning is clear from the verb form or context. So both are possible:

• Kad bi on imao više strpljenja...
• Kad bi imao više strpljenja...

Including on gives extra emphasis or contrast, something like:

• If he had more patience...
• possibly with a nuance of he, specifically

So on is not required grammatically, but it can be used for emphasis.

Because više normally requires the genitive case.

The noun strpljenje means patience, and its genitive singular is strpljenja.

So:

• više strpljenja = more patience
• literally: more of patience

This is very common in Croatian:

• više vremena = more time
• više novca = more money
• više vode = more water

So after više, learners should often expect the genitive.

Mu means to him.

It is the dative singular clitic form of on. The verb smetati works with a dative experiencer — the person who is bothered goes in the dative.

So:

• smetati nekome = to bother someone
• mu smetaju pogreške = the mistakes bother him
• literally: the mistakes are bothersome to him

This is different from English, where we usually make the person the direct object:

• The mistakes bother him

But in Croatian, with smetati, the person is in the dative, not the accusative.

Because the verb agrees with male pogreške, which is a feminine plural subject.

The noun is:

• pogreška = mistake
• plural: pogreške

Since male pogreške is feminine plural, the participle in the conditional must also be feminine plural:

• smetale

Compare:

• Mala pogreška bi mu smetala. = A small mistake would bother him.
• Male pogreške bi mu smetale. = Small mistakes would bother him.

So smetale matches the gender and number of the subject.

Here, male pogreške is the subject of the sentence, so it stays in the nominative plural.

The structure is:

• male pogreške = the thing doing the bothering
• mu = to him
• smetale = would bother

So literally:

• small mistakes would not bother him so much

The negation ne bi does not change the subject into another case here.

The confusion often comes from other patterns, especially with direct objects and certain verbs, but smetati does not take male pogreške as a direct object here. It is the nominative subject.

Toliko means so much, that much, or to such a degree.

In this sentence:

• ne bi mu toliko smetale = would not bother him so much

It modifies the verb phrase and shows degree.

Similar examples:

• Ne brini toliko. = Don’t worry so much.
• Zašto toliko radiš? = Why do you work so much?
• Nije toliko važno. = It’s not that important.

So here it adds the idea of to that extent.

Yes, Croatian word order is flexible, but this version is very natural.

A few things are happening:

1. ne bi stays together as the negated conditional particle
2. mu is a clitic, so it tends to appear early in the clause
3. the subject male pogreške can come later for a natural flow

So:

• ne bi mu toliko smetale male pogreške

is a normal and smooth sentence.

Other possible orders may be grammatically possible, for example:

• Male pogreške mu ne bi toliko smetale.
• Ne bi male pogreške mu toliko smetale. — much less natural

Croatian clitics like mu have special placement rules, so learners should pay attention to them. In practice, putting mu early in the clause is usually safest.

Smetati is an imperfective verb meaning things like:

• to bother
• to disturb
• to annoy
• to be in the way

Its key pattern is:

• nešto smeta nekome = something bothers someone

Examples:

• Buka mi smeta. = The noise bothers me.
• Dim mu smeta. = Smoke bothers him.
• Sitnice joj ne smetaju. = Little things do not bother her.

So in your sentence:

• male pogreške = what bothers
• mu = the person affected

That is why the sentence is built differently from the most common English pattern.

It expresses an unreal or hypothetical situation.

The speaker is not simply saying that he has more patience. Instead, the speaker imagines a different situation:

• If he had more patience, small mistakes would not bother him so much.

This is similar to the English second conditional.

So the sentence implies that, in reality, he probably does not have enough patience, and because of that, small mistakes do bother him.

Yes. Croatian has several natural ways to express this same idea.

For example:

• Da on ima više strpljenja, male pogreške mu ne bi toliko smetale.
• Kad bi imao više strpljenja, male pogreške mu ne bi toliko smetale.

These are very close in meaning.

The original sentence is perfectly natural, but learners should know that Croatian often allows more than one way to express hypothetical conditions.

A natural translation would be:

• If he had more patience, small mistakes wouldn’t bother him so much.

You could also say:

• If he were more patient, small mistakes wouldn’t bother him so much.

The second version is a bit freer, because it turns having more patience into being more patient, but it expresses the same idea naturally in English.