adopted filipina searching for birth mother in Philippines

my mother's name was Lida Tampos Tumbagahan. She lived in Upper Bicutan, Taguig, Rizal when I was born in 1981. She was 35 when she had me. I don't know if she would still still be alive...I'm interested in finding her and my two older biological siblings. I believe that they were put up for adoption also. my mother told me of an older biological sister who was not adoptable because they could not find any papers on her. I want to know if any of my siblings were adopted or if they have made it to America. Any help would be great!