Dictionaries, indeed, translate якраз as actually. The problem is that both якраз and actually have several different meanings that do not perfectly match:
Actually (1) = really; in fact;
I will check what you're actually doing.
A good Ukrainian equivalent for this meaning would be насправді.
Actually (2) = the truth is; surprisingly:
I thought he's tall. Actually, he's short.
Here, actually = якраз.
As you may expect, words that have several meanings would not always retain all these meanings when translated.
Ukrainian якраз has a certain overlap with the English one, but not precisely. I believe it is better to explain it with short dialogues.
Якраз (1) = right at the moment; right at the opportunity.
— You said he will go to the shop.
— You caught me right at the moment when he is in the shop. — Він якраз у магазині
— Let's go to a neighboring town.
— Good idea, I just wanted to take a photo of that covered bridge in the midway — Я якраз хотіла зробити пару знімків того критого мосту по дорозі.
Note that він якраз у магазині can be the opportunity, too:
— I forgot to buy milk.
— Call him to buy it for you. He's at the shop right now.
Якраз (2) = on the contrary; surprisingly;
Imagine a dialog:
— I understand her.
— No, you said don't understand anyone.
— (yes, I agree that I don't understand anyone, but) I do understand her nevertheless. — Якраз ії я розумію
Якраз (3) = fit for
There's one more meaning of якраз, just for completeness:
These shoes fit for me — Ці туфлі мені якраз.