You have to scroll down the theif skills to see all the options (like "traps" that is really down in there) that you can get.
Potions of master thievering can be found easy and they give a great bonus to steal skills and you only few items are worth to steal in the game (like scrolls for the mages) and there are (almost all) in the stores.
I dont really understand the diference of "hide in shadows" and "move silency" but I think that "hide in shadows" is better that "move silency" but its a good idea to have over 75% in both for be a effective scout.
You see, you cannot have both, either you became a scout that can hide and scout for enemys or be a master thief that can steal anything short of being nail down in the floor.
Until ToB, that is...
- Waterdeep city constrution.
- Shadowdale low level adventure module.
- Rashmare /Thay high level adventure module.