I think it's just a Boolean search string. Is it something as simple as
Software developer AND Java AND California ?
Boolean operators are
AND: Z = X AND Y, Z is true only if and only if both X and Y is true
OR: Z = X OR Y, Z is true if and only if one or both of X or Y is true
NOT: Z = NOT X, Z is true if and only if X is false
XOR: Z = X XOR Y, Z is true if and only if one, but not both, of X or Y is true (XOR means eXclusive OR)
Sometimes the NOT operator gets combined as a shorthand - NAND, NOR, and XNOR for NOT AND, NOT OR, and NOT XOR, respectively.
In many forms of input they will have their own characters representing them in shorthand
AND: Usually &
OR: Usually |, but sometimes ^ or +
NOT: !, ~, or -, placed directly before the term to be negated. "Software developer" & java -California
XOR: Usually ^
Search engines don't seem to implement XOR very often or very well. Google treats ^ as OR.
In programming, boolean operators take one of two forms - computations meant to return a logical value, as above, or bitwise operations to generate a new numerical value from one or two input values. Can do things like calculate power-of-2 math very, very quickly.