Why miners try to produce big blocks? What if, does a miner deliberately produce a block with a single transaction (and a coinbase transaction of course) without considering the whole unconfirmed transactions, in order to gain the reduce of network latency advantage or for some other purpose?
Why miners try to produce big blocks?
Because transactions pay fees. The more transactions they include, the more fees can be collected. They prioritize transactions with higher feerate to maximize this.
What if, does a miner deliberately produce a block with a single transaction without considering the whole unconfirmed transactions, in order to gain the reduce of network latency advantage or some other purpose?
Some do that (though mostly because they just received a new block, and haven't had the time to construct a valid set of transactions on top).
In recent times, the argument for faster propagation also does not apply very much anymore. Techniques like Compact Blocks (BIP152), the Relay Network, and FIBRE can efficiently transmit blocks as long as they mostly consist of transactions that were seen before. This almost entirely removes the effect of size from the equation.
A miner would want to include a lot of transactions in a block in order to collect all of the transaction fees associated with the transactions.
However, as alluded to, miners don't have to include transactions in their blocks if they don't want to.
Additionally, a miner may choose to include transactions with transaction fees and exclude transactions without transaction fees (as users can choose whether or not to include a transaction fee in addition to the size of the transaction fee).