Since you already know the year and street of the transactions, this LA County website may lead you to the information you seek:
Los Angeles County Assessor's Office - Home Page
Many counties have an online tract/property number map database in which you can click individual lots (for which street addresses may be listed) and get the names of current owners of record, and recent transaction dates and values.
It's rather tedious process; I've done it for neighboring lots in King County (Seattle area) WA, but it works. I have not tried it for the LA area.
I don't know if your last question was addressed to me. I was hoping you would be able to find the names of buyer and seller and with an online search of county records. There might be a realtor in your area who could help.
I will see what I can find out online using a LA County address where I used to live, and post specific suggestions IF I am successful.
Using a street name where i used to live in Gardena, I was able to get an area map that shows property ID numbers associated with that and neighboring lots online, using the website I mentioned before. Clicking individual properties also shows assessed values, certain highlighted properties in the area that have sold within the last two or three years (not five), and what they soid for. It does not list the buyer's or seller's names. For this, you would have to visit a County Records office. The branch office where the records are kept is named.
There is an LA County online service available for a rather high fee that provides additional information about the property, including the current owner' name. For more about this, see Los Angeles County Assessor's Office - Online Property Database Access
I think your best bet is to call the office of the assessor and then visit the appropriate record office in person. As I said before, a realtor who subscribes to the County online record file may be willing to help.