您能帮我看（kan4）一下电脑吗？我要出去一会儿，马上就回来。

你可以照看一下我的电脑吗？或者 你可以帮我看（kan1）一下电脑吗？看kan4 means look or see, but 看kan1/看kan1守 , means guard and lose freedom, like prisoners or the one is punished or kidnapped. So it is not suitable to use it in this case.

It will be more polite to add" 請問" because you want to ask for help from others. It can be請問可以幫我看一下or 顧一下電腦嗎? 看守is more likely to be very careful to watch someone or something, but you just wanna ask someone to do you a favor to watch your laptop for a short time. Hope my answer can help you!

你可以帮我看一下我的电脑吗？ 一般不会用看守这个词

看守 is too big and not suitable for this sentence. We use 看守 in a prisoner is captured and watched by the police. You can just use the verb 看 with 'the first tone'. 看 pronounciate with the first tone means to watch over, pronounciate with the fourth tone means to look or see. 你可以帮我看一下电脑么？