Asians pronounce 'people' as 'peopo'

I am from South West England and I don't pronounce the 'l' in 'people' etc. I don't pronounce it 'peepo' though, I don't round my lips or flatten my tongue. Even if I do pronounce it, for emphasis perhaps, I use what I believe is called a 'dark l'. My mother is Irish and does pronounce the 'l'. In an Irish accent the tip of the tongue touches the roof of the mouth just behind the teeth.

Chinese speakers don't pronounce the 'l' because there is no 'pl' sound in Chinese. I don't speak Vietnamese so I don't know if that's the same for you.

You are right, though. It's not important for you to pronounce the 'l' to be understood (which is the most important thing) and if you don't make too much of an 'o' sound at the end, it's unlikely any one will notice.

Similarly, I recommend that my students who struggle with the 'ths' sound at the end of 'clothes', simply say 'close'. In fact this is easier (certainly for British English speakers) to understand than 'clothe - es'.