"The flames ran along the deliberate rows of vines, like longed curved fingers reaching for the horizon, lighting the night sky" (pg. 42) It means that the fire's flames were growing and becoming larger, while taking the vines and Papa's property and turning it all into ashes.
"But as soon as she reached a mountain, she was headed back down into a valley again. Would she ever escape this valley she was living in? This valley of Mama being sick?" pg. 160 The mountains and valleys are supposed to represent the ups and downs in life. For instance, Mama being sick is a valley in Esperanza's life, while she's had happier memories.
"A thick tule ground fog that hugged the earth settled in the valley, surrounding them' as if they stood within a deep gray cloud." (pg. 167) It means that the fog was very close to the ground and the fog was touching the ground. It also meant that when they all were out there it was really foggy.