Learn Danish: Jeg forstår ikke hvor hun finder forklaringen. - I do not understand where she finds the explanation.

Because this is an indirect question. The main phrase is Jeg forstår ikke, and the question hvor hun finder forklaringen is embedded inside it. In Danish, indirect questions act as subordinate clauses, which means they use normal, straight word order (Subject-Verb) rather than the inverted word order of a direct question.

How would you ask the direct question: Where does she find the explanation?

You would flip the subject and verb to make it a direct question: Hvor finder hun forklaringen? Notice how our example sentence changes this back to the straight hun finder word order because the question is indirectly connected to the main sentence.

Where would you put an adverb like altid (always) in the second part of this sentence?

It would go between the subject and the verb: hvor hun altid finder forklaringen. Because the indirect question is a subordinate clause, central adverbs go before the verb. Contrast this with the main clause at the beginning of the sentence, where the adverb ikke comes after the verb (forstår ikke).

How does the word forklaringen get its meaning of the explanation?

The base noun is en forklaring (an explanation). In Danish, you make a noun definite (changing it from an to the) by moving the article to the end of the word as a suffix, which gives us forklaringen.