雪解け: snowmelt and signs of a thaw in a relationship
Read 雪解け in soil beginning to appear on a mountain path and signs of improving relations. Distinguish a physical process and its beginning from a figurative sign of change.
Soil appearing as snow melts
雪解け（ゆきどけ） means snowmelt or thaw. 「雪解けが進み、山道の土が見え始めた。」（As the snow melted, soil on the mountain path began to appear.） 雪解けが進み describes the melting progressing, while 山道の土が見え始めた describes soil on the mountain path beginning to appear.
山道の土 is what began to become visible. That beginning has a narrower scope than all snow on the entire path having disappeared. Follow the process and the beginning stated in the sentence.
Signs in two people's relationship
「二人の関係に雪解けの兆しが見えた。」（There were signs of a thaw in the relationship between the two people.） 雪解け is figurative within 二人の関係, the relationship between two people. It describes signs of a thaw in their relationship, rather than actual snow or their bodies melting.
In 雪解けの兆し, 兆し names an indication of change. Indications of improving relations differ from completed reconciliation. The sentence gives no account of a full reconciliation having taken place.
The target and the stage of change
The first example connects snowmelt on a mountain path with soil becoming visible. The second connects a relationship with signs of a thaw. 山道 and 関係 help identify the physical and figurative senses of the same word.
見え始めた marks a beginning in the path example, and 兆し marks a sign in the relationship example. Read visible soil and indications of improvement without expanding them to the disappearance of all snow or completed reconciliation.
Does 「二人の関係に雪解けの兆しが見えた。」 establish actual snowmelt or completed reconciliation?
Show the answer and why
It describes figurative signs of a thaw in the relationship. It concerns neither actual snow nor bodily change, and signs alone do not establish completed reconciliation.