Chinese languages

I heard these on Taiwanese TV.

o
lo
ei
lei

In my head i just pretend they're like a/ya and le, but if someone could clarify their meaning and usage to me that'd be great.

The usage le la also perplexes me. Sounds like a "le" would be enough. "ta zhidao le la!"

These are not standard Mandarin particles. This is what refered to as Taiwan Guoyu or "Taiwanese Mandarin". They don't indicate anything, just sounds.

"ta zhidao le la!" can be heard in mainland. The additional la means , you should not ask any more , he has already known it. It is used in some contexts.