Several times happened to me....

I'd carry nearly 15 over items on hand, with some gold. And found a good deal at a "unknown" located shop somewhere in the huge map. Very happy to see the price it offer...but when I prepared to put gold and buy it....the chest ended up filled with others item. Some are nice item, some aren't, those item usually not the item suppose to be in that particular "trade chest"

So, in this situation, can i take those item???

Some situation where the item remains there for hours..

What I usually do is make a pe, stating that someone forgot to take their stuff from a trade chest.

A mod will then hawkeye the chest to see who owns the items and undergo proper actions.

To answer your question, I wouldn't take the items out since I have seen people getting a ban for it.