Finally to day the tools set arrived but unfortunately I found 13 sets missing plus all the samples your boss sent me.

我不知道

原句没有标点 啊, ME给加上了. 哈------
Finally today the tools set arrived, but unfortunately I found 13 sets missing ,plus all the samples your boss sent me.

今天这批工具(货物)终于到货了, 但不幸的是缺13套, 其中包括你们老板发来的样品.

工具设备已于今天收到，不幸的是少了13套/件（包括你们老板发给我的所有样品）

唉...

哪国人写得英语啊这是

Finally to day the tools set arrived but unfortunately I found 13 sets missing plus all the samples your boss sent me.
it should be : Finally today the tools set arrived but unfortunately I found 13 sets missing plus all the samples your boss sent me.
it should be translated like this:  今天终于收到工具套件了，但是很不幸，我发现少了13件，还有你们老板寄给我的样品也没有了。
重要的是plus，不是指包括在13套里，而是额外的样品。