Can South Korean passport holder temporarily living in Vietnam enter EU countries?

However, I found the entry requirement of each country to be quite unclear if me being a Korean passport holder is enough to enter the country or I should have stayed in Korea before coming to these EU countries.

Each EU country has its own policy, but looking at the case of France for example, being a Korean passport holder is not enough (quote from IATA and echoed by https://reopen.europa.eu/en/map/FRA):

• passengers arriving from Andorra, Australia, Canada, Georgia, Japan, Korea (Rep.), Monaco, Morocco, New-Zealand, Rwanda, San Marino, Switzerland, Thailand, Tunisia, United Kingdom, Uruguay, Vatican City (Holy See) or an EEA Member State;

which needless to say, makes the most sense.

Full IATA information for France:

France Published 01.08.2020

1. Passengers are not allowed to enter.

• This does not apply to:
• nationals of France, if not arriving from French Guiana or Mayotte, and their spouses and children;
• British nationals and nationals of Andorra, Monaco, San Marino, Switzerland, Vatican City (Holy See) and an EEA Member State if not arriving from French Guiana or Mayotte; and their spouses and children;
• passengers arriving from Andorra, Australia, Canada, Georgia, Japan, Korea (Rep.), Monaco, Morocco, New-Zealand, Rwanda, San Marino, Switzerland, Thailand, Tunisia, United Kingdom, Uruguay, Vatican City (Holy See) or an EEA Member State;
• passengers with a residence permit issued by Andorra, Monaco, San Marino, Switzerland, United Kingdom, Vatican City (Holy See) or an EEA Member State if not arriving from French Guiana or Mayotte;
• merchant seamen if not arriving from French Guiana or Mayotte;
• students if not arriving from French Guiana or Mayotte.

2. Passengers arriving from Bahrain, Panama, USA or United Arab Emirates must have a medical certificate with a negative Coronavirus (COVID-19) PCR test result issued at most 72 hours before departure.

• This does not apply to passengers younger than 11 years.

3. Passengers arriving from Algeria, Brazil, India, Israel, Kuwait, Madagascar, Oman, Peru, Qatar, Serbia, South Africa or Turkey must have a medical certificate with a negative Coronavirus (COVID-19) PCR test result issued at most 72 hours before departure. Passengers without a medical certificate must take the test on arrival.

• This does not apply to passengers younger than 11 years.

4. A completed International Travel Certificate must be presented prior to boarding and to immigration upon arrival or when transiting France. The certificate can be obtained at consulates or at https://www.interieur.gouv.fr.

• This does not apply to passengers arriving from Andorra, Australia, Canada, Georgia, Japan, Korea (Rep.), Monaco, Morocco, New-Zealand, Rwanda, San Marino, Switzerland, Thailand, Tunisia, United Kingdom, Uruguay, Vatican City (Holy See) or an EEA Member State.

5. Passengers must complete a declaration on honor to state that they do not have symptoms of Coronavirus (COVID-19).
6. Passengers are subject to quarantine or isolation.

I successfully entered Greece from Vietnam without any problem. (the immigration officer didn't ask anything where I am coming from)

As of 10.08.2020, as a South Korean citizen and resident flying from Vietnam, you can enter the Schengen Area through the following countries:

• Czechia
• Denmark
• Estonia
• Finland (if flying directly from Cyprus, Japan, South Korea or Thailand)
• France (if flying directly from Bulgaria, Canada, Croatia, Cyprus, Georgia, Ireland, Japan, Morocco, Romania, South Korea, Thailand, Tunisia or the UK)
• Germany
• Hungary (if flying directly from Bulgaria, Canada, China, Croatia, Cyprus, Ireland, Japan, Romania, Russia, Serbia, South Korea the UK or the US)
• Italy (if not having spent the past 14 days in Algeria, Armenia, Bahrain, Bangladesh, Bosnia and Herzegovina, Brazil, Chile, Dominican Republic, Kuwait, Moldova, Montenegro, North Macedonia, Oman, Panama, Peru or Serbia)
• Latvia
• Lithuania
• Luxembourg
• Malta (if flying directly from Bulgaria, Croatia, Cyprus, Ireland, Jordan, Morocco, Romania, Tunisia, Turkey, the UAE or the UK)
• Netherlands
• Poland (if flying directly from Albania, Bulgaria, Canada, Croatia, Cyprus, Georgia, Ireland, Japan, Montenegro, Romania, South Korea or the UK)
• Portugal (if flying directly from Algeria, Bulgaria, Canada, China, Croatia, Cyprus, Ireland, Morocco, Romania, Tunisia or the UK)
• Slovakia (if flying directly from Bulgaria, Croatia, Cyprus, Ireland, Montenegro, or the UK)
• Slovenia
• Spain (if flying directly from Bulgaria, Croatia, Cyprus, Ireland, Romania or the UK)
• Sweden
• Switzerland (if flying directly from Bulgaria, Canada, Croatia, Cyprus, Ireland, Japan, Morocco, Romania, South Korea, Thailand Tunisia or the UK)