an integral involves mutiply of two Kummer Confluent Hypergeometric function

Question

i met an integral involving the mutiply of two Kummer Confluent Hypergeometric functions as follows: $$\int_{ - \infty }^\infty {\frac{1}{{{x^\alpha }{{\left( {x + k} \right)}^\beta }}}{}_1{F_1}\left( {{a_1};{b_1};\frac{{{c_1}}}{x}} \right){}_1{F_1}\left( {{a_2};{b_2};\frac{{{c_2}}}{{x + k}}} \right)} dx$$ where ${}_1{F_1}$ is the Kummer Confluent Hypergeometric function, and $\alpha ,\beta ,{a_1},{a_2},{c_1},{c_2} > 0$. Thanks for your help in advance.