I play $1/2 or $1/3 NL. Very seldom does it fold to me once I am in middle or late position. I understand that since it did not fold to me the opening hand ranges do not work but with no information about the villains I am not sure what hands I should raise with (I understand the calling hands) when I have early or middle position limpers in front of me. Also, does it change if I have several limpers vs. just 1 or 2?