Throwin sand, is short for-Throwin sand in my eyes.

This term is used to describe people who tell others stories or gossip but leave out vital information in the process.
or
A person who has said something he/she/it shouldn't, but it is too late cover up the rest of the story

in other words...
A nigga who tries to hide info.
Man tell me what happened, quit throwin sand.

I always tell you everything, I don't never be throwin sand.
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