what gives bread its tast is it salt or what sometimes bread taste very bland
Read up on slow fermentation and overnight fridge retardation. Basically the slower/longer your bread rises, the tastier it will be.
There are many many threads on TFL regarding this.
I agree with dwcoleman, but salt is a flavor enhancer. Without it the bread will have less flavor.
sometimes bread tastes very bland
There's nothing intrinsic about bread that requires it to taste bland ...it does happen a lot though. Making bread not taste bland is a big part of what TFL is all about. Lots of different factors contribute (you probably won't find a one-size-fits-all answer). Some methods are honest, others are "cheating" (for example "just add more sugar").
As a very rough rule of thumb, all the things that allow commercial operations to produce bread easier/faster/cheaper also mean less taste. You could think of it sort of like a teeter-totter with "business" on one side and "taste" on the other side, or you could think of it as sort of analogous to storebought vs. homegrown tomatoes, or... You can get some very tasty breads indeed from specialty bakeries, but you'll pay lots more than supermarket prices for them.
Salt and sugar compliment each other. The craft of the baker is to use their skill to blend the two together.