If a little air bubble from iv line into my vein, is it my body could remove the air bubble out my body soon? not inside forever ?

No harm, no worry: Small amounts of air dissolve into the blood very rapidly. Your blood naturally contains lots of dissolved oxygen, nitrogen, and carbon dioxide. A teeny bit more won't hurt. You would have to rapidly inject a whole lot of air into a vein do do harm. Don't worry about it.

Some basics: I agree with Doctor H. . It would take a person shoving a supersized syringe full of air into a vein in one fast push to affect you in a negative way. Even that would likely do little.