Eliezer was given very clear guidelines in his quest to find a wife for Yitzchak. He must absolutely not consider any girl from the Canaanite families.
The question was asked about the family of Betuel. Why was it preferable to go to Avraham’s birthplace when they were also idol worshippers and not G-d fearing people.
Rav Asher Weiss answered this question by saying that the character of Yitzchak’s perspective bride was what was important.
The Canaanite people were inherently evil and of a low moral standard. Their daughters would not be capable of understanding and encouraging a Tzadik such as Yitzchak. Their bad character could potentially bring him down.
If Betuel, the father of Rivka, had a problem with idol worship, that was something that could be remedied. Bad character is very difficult to cure.
This is why it was necessary for Eliezer to make the long journey to seek out someone appropriate for his master.
This also explains why Eliezer looked for specific signs in a young maiden. He was looking for acts of kindness. He wanted to see that she showed compassion for the camels. He was looking for a girl with good character.
This should be the same criterion when looking for a spouse. We are not be fooled by external beauty or superficialities. It is what is on the inside that matters. A Jewish home should be one of Chessed. Along with Torah study, this is the foundation of a Jewish home.
Avraham Avinu understood this and passed on this lesson to Eliezer as well as future descendants.