Tanha is liking sense-pleasures, liking for becoming and liking for non-becoming. Upadana is clinging for sense-pleasures, wrong views, rites-and-rituals and self-doctrine.

Upadana is at the level of clinging whereas Tanha is mere liking of the above mentioned. Ex: you see an expensive watch in a shop and you start to like it. That is Tanha. That liking leads to wanting it for yourself. That is Upadana. That wanting leads to trying to buy it or trying to steal it. That is Bhava(Karma).

Tanha is liking sense-pleasures, liking for becoming and liking for non-becoming. Upadana is clinging for sense-pleasures, wrong views, rites-and-rituals and self-doctrine.

Upadana is at the level of clinging whereas Tanha is mere liking of the above mentioned. 

Ex: you see an expensive watch in a shop and you start to like it. That is Tanha. That liking leads to wanting it for yourself. That is Upadana. That wanting leads to trying to buy it, buying it or trying to steal it, stealing it. That is Bhava(Karma).