If you find something lost, don't post it online.

There are small things that may not require much attention when in Vietnam, but if you're abroad (especially in Europe), not paying attention could cost you a lot of money or lead to significant troubles.​

Pay attention to avoid trouble​

In Vietnam, we occasionally see photographs of lost identification papers shared on online groups with calls for help to reunite them with their owners. However, if you're in European countries, doing so could land you in legal trouble.

Recently, in the forum Vietnamese students in Finland, a heated debate arose when A. found a passport belonging to a fellow countryman. A. posted a photo of the passport in the Vietnamese group hoping the owner could quickly get it back. As a result, A. received threats of legal action from the person who lost the passport! Finland and other European countries enforce the General Data Protection Regulation (GDPR). Thus, disseminating someone else's personal information online is prohibited.
In this case, the correct action after finding lost items is to turn them in to the police station; if you receive a misdelivered letter, return it to the post office.

Throwing away trash, remember to delete personal information​

Q.M. expressed frustration over a £150 (nearly 4.9 million VND) fine he received along with a picture of a cardboard box with his name and address that was left right in front of the trash bin. It's not that he intended to dispose of waste incorrectly; it’s likely the garbage collector dropped it while transporting. Q.M. asked friends in the Student Employment Group in the UK for advice on how to deal with this fine: "I didn’t dispose of trash improperly, but having to pay this fine is really ‘bitter’!".
According to friends' advice, Q.M. could file an appeal. If Q.M. does not appeal and simply ignores paying the fine, the amount may be transferred to a debt collection agency, becoming a bad debt recorded in his credit history. Q.M. and friends also learned another note: for packages with one's name and address, they must be removed or obscured before disposal!

House keys – an essential item!​

In Vietnam, losing a key is a minor issue: call a locksmith to unlock the door for about 200,000 VND and have a spare key made for only about 10,000 VND. However, for international students in Finland, losing a key means incurring considerable costs.
When students receive their rooms, the rental company provides a key (usually a master key). This key is used to open multiple doors: private rooms, shared apartments, buildings, trash rooms, laundry rooms, etc. If lost, you might have to pay from 300 euros (around 8.3 million VND) or more. Nguyễn Thủy, a student in Finland, stated she once had to pay up to 600 euros (16.6 million VND) because after losing her key, the locksmith had to adjust the lock.
New students who are not familiar with the locking system here can easily "run into trouble." Just a door slamming shut can automatically lock it. Some students leave their keys inside, go out, and the wind slams the door shut, or forget the keys when leaving the house, with locksmith call fees ranging from 100 to 195 euros (2.7 to 5.4 million VND). So, the simplest solution is to attach the key to a lanyard!

Proactively monitor your working hours​

Each country has regulations on the maximum working hours for international students; exceeding this limit is not permitted. Recently, in the Student Job Search Group in the UK, a student recounted his frustration about being misreported by his restaurant employer for working more hours than he actually did: "I only work an average of 8-10 hours/week. Normally, they pay via bank transfer, but last month they offered to pay in cash, and I thought nothing of it and just agreed. It was only now that I discovered the restaurant reported double the hours I actually worked…".
The restaurant owner does this to inflate costs, thus reducing taxes more significantly, but it creates trouble for the student: "The problem is that I also have other part-time jobs, totaling the maximum allowed 20 hours/week, so misreporting like this will affect my visa status. I plan to quit that job immediately because I’m quite anxious about it!".

Source: https://thanhnien.vn/nhat-duoc-cua-roi-dung-dang-len-mang-185240828094058824.htm