heres a theme i found in The Bonesetters Daughter by AMy Tan, my teacher said i should expand this but quite frankly, I'm stuck.

-Mother Daughter Relationships: Consists of three generations in this case, from earliest: Ruth, LuLing and Precious Auntie. Although taken for granted most of the time, a mother’s love is forever and is in the best interest of the daughter for her mother to teach her about life. (“I’ve been that way with my mother all my life...she remembered she had been eluding her [mother].”(p37) Her mom tries her best to keep Ruth from harm, but Ruth evades her mom’s nagging)

how should i expand that?
First off Amy Tan = Grrrr. Try to find something that isn't clearly obvious in the story. Nobody would challenge the fact that you are stating here. Maybe compare some of the other influences women had on Ruth besides her mom. Something that isn't really that good for her versus "Mom's tough love"
what my teacher means is expand that to make it more general and applicable to teh world. like examples she gave us that got a perfect score were something like this:
religion:-the practice of religion is futile without a strong belief in the morality behind the religious laws