can a unit claim multiple TEM adjustaments from a single hex for ewxsampe a unit in 21V4 geinf fired at from X4 is it just +1 for either the woods or the wall but not both or is +2 for =1 for the woods and +1 for the wall too?
See B9.31. The wall TEM is not cumulative with other terrain in the hex, such as the woods in your case. In most cases, you can choose which you'd like to use (such as using +2 wood building TEM instead of a +1 hedge TEM, or using a +2 wall TEM instead of the +1 woods TEM). In your example it's +1 either way.
However, things get a bit more complicated where Wall Advantage is concerned.