"'Make sure that you do not take my son back there,' Abraham said. 'The Lord, the God of heaven, who brought me out of my father's household and my native land and who spoke to me and promised me on oath, saying, "To your offspring I will give this land" - he will send his angel before you so that you can get a wife for my son from there.'" NIV translation
We see that Abraham is confident that his servant will get a bride for Isaac because he realizes that this marriage will be arranged by God. He remembered God's promise to him and has faith (trust in Him) that it will be kept. The biblical pattern from Genesis to Revelation is that the Father chooses the bride. This is true even today as God has created a spouse just for each of us and we can have the patience and faith to wait or we can choose to make the selection on our own.
"'If the woman is unwilling to come back with you, then you will be released from this oath of mine. Only do not take my son back there.' So the servant put his hand under the thigh of his master Abraham and swore an oath to him concerning the matter." NIV translation
Abraham trusted God enough to tell his servant that he was released from the oath if the woman did not come back with him.
This reminds us that it is totally a work of God in both the man and the woman. God would have to put it in the woman's heart to accept the marriage proposal. She would not be forced to marry Isaac.
"Then the servant left, taking with him ten of his master's camels loaded with all kinds of goods from his master. He set out for Aram Naharaim and made his way to the town of Nahor." NIV translation
The servant left but took a large part of Abraham's wealth with him. This was to be the bride price but it was not to buy the woman and make her a slave. Instead, it was an assurance of the man's ability to care for the woman. No dad would want his daughter to marry a bum that couldn't provide for her and this was meant to make it clear that the man (Isaac) had the necessary means. This is also a picture of the fact that Jesus would give the ultimate price for His bride which is the church. We can be assured that He has the wealth to take care of our every need!