why westerners believe in God so

i met a lof of americans, white americans.they often talk about God, even every meal, they often say, "thanks, God , thank for giving us delicious food"even in science field in western countries, they divide the word into two parts, one is our reality world, in this world, they research and idscover the secrets of the objective world. but the other world, even some famous scholars and scientists assert that we can not see the truth, unless we have "God's view". they leave the unsolving prolblems to God.why, why?

I am going to guess I know more amerikans than you do considering I have lived there for 24 years and hung out pretty exclusively with amerikans in addition to being one.
Now in my total experience i would say I have been party to someone thanking god for a meal perhaps 10 times.

God holds no reverence in my home country nor do we worship more than average.
You clearly know nothing about the US or its people so I will be happy to educate you. Amerikans mention god more than chinese because they didnt have a cultural revolution to try and exterminate them. As opposed to China which is officially atheist the US gov refuses to comment on god holding that for people on their own to decide.

The US is less religious than many parts of the world, Thailand, SKorea, India, Greece, Italy, Mexico to name just a few.

The West is not only the U.S. or North America. It includes Europe as well. In vast parts of Europe r3l1g10n plays no - or an insignificant role. Europe had bad experience with r3l1g10n and many people only attend r3l1g1ous service once a year (X-mas) or never at all. There is also a difference between North and South. Scandinavia is far less r3l1g1ous than Austria, Italy, Hungary, Poland or Spain/Portugal. Last but not least, in NON Roman Catholic nations (Scandinavia, The Netherlands, the Northern half - and East of Germany), church does not interfere in people's life. This is of course different with the church of Rome (Vatican).