On China and Taiwan belching its a good manner, because it shows to the chef that food was delicious.
SHOW YOUR SOLES
Watch out if you show your soles on middle or fast east, its consider as an insult, like for example, resting your feets up.
SWAPPING BUSINESS CARDS
Wrap or write over an presetation card on asian countries or even put in your pocket without seen it its disrespectful.
If you do it a crushing handsheke on Phillipines it’s a agression sign for them.
In Japan and Korea, a tip is considered an insult, they see it as you making look at them as beggars.