Generate filter criteria based on multiple field combinations
Usually I tell at code reviews that saving a level of indentation is a good thing, but in the case of your code I wondered why you placed three times the same condition because I had a hard time to notice the !'s so I would suggest to take a different route, otherwise you will be confused in half a year as well.  

I would use a `if..else if´ like so  

if (searchConditions.FeeTypeId.HasValue)
{
    if (string.IsNullOrEmpty(searchConditions.FeeTypeName))
    {
        return new { TenantId, FeeTypeId = searchConditions.FeeTypeId.Value };
    }
    return new { TenantId, FeeTypeId = searchConditions.FeeTypeId.Value, searchConditions.FeeTypeName };
}
else if(string.IsNullOrEmpty(searchConditions.FeeTypeName))
{
    return new { TenantId };    
}

return new { TenantId, searchConditions.FeeTypeName };