A proverb warning not to trust strangers easily; be cautious and assume the worst when meeting people.
詐欺が多いので、母はいつも『人を見たら泥棒と思え』と言って私に注意を促す。
Because there are many scams, my mother always tells me, "Assume everyone you meet is a thief," and warns me to be careful.
新しい取引先とはまず慎重に接したほうがいい。人を見たら泥棒と思えという考え方も時には必要だ。
It's better to deal cautiously with new clients. The attitude of 'assume the worst' can sometimes be necessary.
夜道で見知らぬ人が近づいてきたら、無警戒で話しかけないで。人を見たら泥棒と思え、だよ。
If a stranger approaches you on a dark road, don't speak to them unguardedly. Remember: assume people are thieves.