The first means "What thoughts are going through your head right at this second?" The second means "What is your opinion (on the matter we've been hearing about or discussing)?"

So if there's a particular matter under discussion and you expect someone has or should have an opinion, you ask "What do you think?"

If there's no particular matter under discussion or you suspect someone is still thinking and doesn't have an opinion yet, you could ask "What are you thinking?"
Thanks.
Excellent post.
thank you
nice post
thanks
nice work
tnx
Talent guys. Really you are genius.
thank you
True indeed
yes
good job
its ok
yes , that's the point
thank you
Very nice post
stay with me for next post
creative post
stay with me
good thinking..
thank you very much
good post
thanks
good job done.
thanks
wow...impressive!!!
thanks
nice
thanks
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