Laravel multiple column eloquent search query

Simply chain where for each field you need to search through:

// AND
$results = SomeModel::where('location', $location)->where('blood_group', $bloodGroup)->get();

// OR
$results = SomeModel::where('location', $location)->orWhere('blood_group', $bloodGroup)->get();

You can make it easier to work with thanks to the scopes:

// SomeModel class
public function scopeSearchLocation($query, $location)
{
  if ($location) $query->where('location', $location);
}

public function scopeSearchBloodGroup($query, $bloodGroup)
{
  if ($bloodGroup) $query->where('blood_group', $bloodGroup);
}

// then 
SomeModel::searchBloodGroup($bloodGroup)->searchLocation($location)->get();

Just a sensible example, adjust it to your needs.