Advertising from bloggers is a very effective way to promote, but finding them is a headache for Instagram administrators. Let's talk about some of the search methods.
If someone you know has a blogger that has been tested on personal experience, grab it and don't even think about it! Such recommendations should be protected and passed on to descendants.
You can also use the search for Instagram by keywords and choose from the options offered what your heart went to.
By the way, there is an arrow in the profile header, by clicking on which you can see similar accounts.
There are also the so-called "exchanges" of bloggers. They are convenient in that all offered accounts are sorted by topic and advertising cost. However, such "exchanges" have a drawback: not everyone monitors the quality of the offered pages.
If you need a blogger who writes, for example, about sports, you can enter the following into the Google search bar: site: instagram.com “k followers” (# sports) and enjoy a selection of accounts on a given topic. After the #, you can insert any topic that interests you and choose who you would like to work with.