When starting your profile on Thumbtack, especially if it's your first business, the tendency is to cast a wide net. Entering services that are loosely related to your field, trying to get as many quote requests as possible.
In reality you want to narrow your parameters as much as possible so that the quotes you receive are a service you can excel in. Make sure you are doing something you are very competent in, something you can show off your excellence in. Make sure you can give them a service that they'll tell their friends about. Word-of-mouth referrals are gold.
I equate the two types of marketing as the difference between hunting with a shotgun vs hunting with a rifle. The shotgun has a wide spread and may graze any number of possible targets, but is far less likely to take any one of them down. Hunting with a rifle means you have to actively target each individual, but you are far more likely to get what you want.
I have found if you respond to your potential client after you have been notified that they have view your quote with just a simple: Thanks for taking the time to view my quote, let me know if I can answer any questions, has been very effective for me.
My tip to pros out there is to keep working on your business. It can be difficult as an individual to get established, and Thumbtack definitely helps with that. But with all the various aspects of your business, not only marketing, my experience tells me that the way to succeed is to keep on trying, to keep working at it: Keep learning, keep getting to know your clients' needs, and keep trying new things. The result will be that you will find the way that really works for you, so that you can thrive.