For your information Bitcoin is not banned in Venezuela in fact the president of this country created their own version of Crypto currency name Petro coin. Your Bitcoin will not be discover by the government because it is decentralize that is why other nation is against of Bitcoin existence but still your transaction will be trace every time you will convert your Bitcoin to fiat in your local exchanges as per government regulation policy but that if Bitcoin is legal in your country but if Bitcoin is illegal in your country then it is very impossible for you to join this investment to earn.

In reality, these laws are extremely hard to enforce.

First of all, it's not actually illegal to have or use bitcoin in Venezuela. In fact, mining is actually completely legal as well, which is better than some countries even. The government has its own crypto as well, so it would make no sense to ban BTC which is the major crypto.

A government can pretty much only trace you down with leads from third party exchanges, etc.. However, even then it'll be hard to actually see for a government whether you hold any BTC and how much BTC you're holding. Practically speaking, it's simply not worthwhile for them on a effort and money basis to enforce these regulations if you're just an average Joe using bitcoin. Again, it's the beauty of decentralization. Governments can't just say one day that they want to shut BTC down and do so, since it's decentarlized.

I think Government cannot control or ban crypto. Even if they ban in your local country you can still buy/sell or trade on international websites.

Well for me the government will discover bitcoin unless their is an investor who report it to the police. And it will trace it because of the information they gave. Government can not control to banned bitcoin from the users. Especially if it gave a big profit to the users.

Just like what @gesdan say Bitcoin can not be trace because it is universal. And it can only trace through the history of your web. And unless you give your bitcoin information online or posting in social media because it can attract to the people who will read it. And the government did not do any actions if you did not break the laws that covers the cyber crime law.

If you have assets on local exchange and often exchange money from local exchange to paper money, the government will easily know you have bitcoins. Keep in mind, when verifying accounts on local exchange you need to include your identity card, this will make it easier for the government to track users of cryptocurrency. Because I know, a local exchange will run if it is approved by the government.

   In my knowledge bitcoin is anonymous ,meaning nobody can trace your transactions even your wallet as long as you didn't give you identity or enter it when you make a transactions. bitcoin is decentralized that no single authority controlled it even the government that's why it is difficult for them to trace your bitcoin without showing your real identity.

They won't be able to find you unless you have signed up for some exchanges that requires personal info or in a KYC. Bitcoin is from a decentralized system so unless you spoonfed the internet with your personal info in connection to your addresses, you will be safe from being tracked down. That is why you should be careful on the things you participate especially because you live in a country where bitcoin is banned.

 No, it is not possible for any government to trace the Bitcoin user because it is decentralized in nature and no inter mediator. It is anonymous only the buyer and seller deals without a third party. The transactions are are recorded in an electronic ledger which is controlled by the blockchain technology. The Bitcoin can be operated through out the world electronically. This is a modern form of economic transition for the benefit of the humanity which will be a contradiction to current concepts for the modern era.

I think it's possible for them to know if you have bitcoins if you have sensitive data linked to your wallet address on the internet

No matter What you do you will be tracked one day and the main cause of it will be when you are going to transfer your Bitcoin into Real world money. As long as you are inside the Bitcoin system yourself and anonymous. Although we are still trackable just like FBI did. The track down the owner of deep web shop and arrested them even though they're using Bitcoin payments this still got succeeded in tracking him.