It's not as simple as you think.

I cannot type Chinese here so please forgive me by using English.
If you send couple thousand dollars in a year, nobody will record and track you. However, if you send three thousand dollars or more every time to the same address and you send money several times a year, you might be already recorded and tracked. The banks have the obligation to report them to the authority. I do not know if anyone remembers the downfall of New York governer Spitzer because of the prostitution scandale. How did FBI find it out? Because he sent money (about 4000 dollars) several times to the same address in a year (???), and FBI started an investigation.

It is my personal opinion, which might be wrong. For reference only.