To say that you’re doing multiple things at the same time (multi-tasking :)), use vừa before the verb
subject + vừa + verb 1 + vừa + verb 2 (+ vừa + verb 3 + vừa + verb 4 … to infinity)
|He||go to||study||go to||work|
Grandpa listens to the radio and reads newspaper at the same time.
To say that something is both so and so (adjective/adverb), use
subject + vừa + adjective 1 + vừa + adjective 2 (… to infinity)
It’s both hot and humid.
Note: When someone tells you Vừa vừa thôi! it means Quit it! at whatever it is that you’re doing (usually when you’re teasing him/her).