I am trying to make a search system for my Next JS API. This API stores some data like fuel prices and fuel station name, etc. Below is the code:

class ApiFeatures {
  constructor(query, queryStr) {
    this.query = query;
    this.queryStr = queryStr;
  }

  search() {
    const keyword = this.queryStr.keyword
      ? {
          $or: [   //Causing the issue
            {
              name: {
                $regex: this.queryStr.keyword,
                $options: "i",
              },
            },
            {
              email: {
                $regex: this.queryStr.keyword,
                $options: "i",
              },
            },
            {
              //I think this is causing issue. Please read down below for more details.
              petrolPumpName: {
                $regex: this.queryStr.keyword,
                $options: "i",
              },
            },
          ],
        }
      : {};

    this.query = this.query.find({ ...keyword });
    return this;
  }

API function of Next JS.

const handler = catchAsyncErrors(async (req, res) => {
      const apiFeature = new ApiFeatures(
          //\/ this function is called without searching
          User.find().select("-role -verified"),
          req.query

      // \/ calling the search function
      ).search();
      const users = await apiFeature.query;
      if (users.length === 0) {
          return res.status(404).json("No User Found");
      }
      return res.status(200).json(users);
});

export default connectToMongo(isAuthenticated(catchAsyncErrors(handler)));

using this function I am trying to fetch data only for the requested query. Example: If the query URL is - http://localhost.com/users?keyword=username then I want list of all the user with that particular user but instead it search for all the user like normal MongoDB find() function does.

**Explaination**
Working of this API
for fuel api
URL in Next JS App = `http://localhost.com/fuelStation`
query URL called = `http://localhost.com/fuelStation?keyword=AbcfuelStation`
Data returned =

  {
    "rate": 50,
    "quantity": 100,
    "amount": 5000,
    "fuelStationName": "Abc fuel Station"
  },
  // Why this is below one? \/
  {
    "rate": 50,
    "quantity": 100,
    "amount": 5000,
    "fuelStationName": "XYZ"
  }