Can Admin see all votings report in periodical form
Can Admin see all voting report in periodical form, user or topic vice voting chart ?
I'm sorry but not. wpForo Polls addon doesn't have backend reporting tools yet. I'll let you know when we start to work on such tools.
Sure, the feature you're asking for is an important feature, but this is not the main purpose of the Polls solutions. Polls are designed to allow people create polls, vote for certain answers and see voting results. Also there is a widget with list of all polls. You have many options to see polls (topics and widgets).
In case you have many polls and it's hard to find the one is mostly voted you should wait for future version releases. The current version is 1.0.0, and as you see this is the initial version. We can't add all polling features in the initial version. All will be added in near future releases. This is already in our to-do list. I have no an exact ETA yet, but will do our best to make it available as soon as possible.