When I want to search, only the first letters of each name appear to me

When I want to search, only the first letters of each name appear to me. For example, if I type the letter A, I do not see all the names that contain this letter. I do not want only the beginning of the name.

The project has connect with the firebase.

this when I try to search

class _ListServicesState extends State<ListServices> {
  var searchText = '';
  @override
  Widget build(BuildContext context) {
    final ref = FirebaseFirestore.instance.collection('Services');
    Query<Map<String, dynamic>> query;
    query = ref.orderBy('title').startAt(
      [searchText],
    ).endAt([searchText + '\uf8ff']);
    return Scaffold(
      appBar: AppBar(
        title: TextField(
            decoration: const InputDecoration(
              iconColor: Color.fromARGB(255, 124, 43, 43),
              hintText: 'Search...',
              suffixIcon: Icon(Icons.search),
            ),
            onChanged: (String value) {
              setState(() {
                searchText = value;
              });
            }),
        centerTitle: true,
      ),
      body: StreamBuilder(
        stream: query.snapshots(),
        builder: (_, AsyncSnapshot<QuerySnapshot> snapshot) {
          if (snapshot.connectionState == ConnectionState.waiting) {
            return const Center(
              child: CircularProgressIndicator(),
            ); }
          
          if (snapshot.data!.docs.isEmpty) {
            return const Center(
              child: Text('No data to be displayed.'),
            );
          }
          var Services = snapshot.data!.docs;
          return ListView.builder(
            itemCount: Services.length,
            itemBuilder: (ctx, index) {
              final Service = Services[index].data() as Map<String, dynamic>;
              final ServiceId = Services[index].id;
              return Column(
                children: [
                  ListTile(
                    title: Text(Service['title']),
                    subtitle: Text(Service['price']),
                    trailing: IconButton(
                      icon: Icon(
                        Icons.delete,
                        color: Color.fromARGB(255, 184, 16, 16),),
                      onPressed: () async {
                        await FirebaseFirestore.instance
                            .collection('Services')
                            .doc(ServiceId)
                            .delete(); }, ),
                  

>Solution :

Try the following code:

class _ListServicesState extends State<ListServices> {
  var searchText = '';
  @override
  Widget build(BuildContext context) {
    final ref = FirebaseFirestore.instance.collection('Services');
    Query<Map<String, dynamic>> query;
    query = ref.orderBy('title');
    return Scaffold(
      appBar: AppBar(
        title: TextField(
            decoration: const InputDecoration(
              iconColor: Color.fromARGB(255, 124, 43, 43),
              hintText: 'Search...',
              suffixIcon: Icon(Icons.search),
            ),
            onChanged: (String value) {
              setState(() {
                searchText = value;
              });
            }),
        centerTitle: true,
      ),
      body: StreamBuilder(
        stream: query.snapshots(),
        builder: (_, AsyncSnapshot<QuerySnapshot> snapshot) {
          final List Services = snapshot.data!.docs;
          Services.removeWhere((element) {
            final Map<String, dynamic> _element = element.data() as Map<String, dynamic>;
            return _element['title'].contains(searchText) == false;
          });
          if (snapshot.connectionState == ConnectionState.waiting) {
            return const Center(
              child: CircularProgressIndicator(),
            ); }
          
          if (Services.isEmpty) {
            return const Center(
              child: Text('No data to be displayed.'),
            );
          }
          return ListView.builder(
            itemCount: Services.length,
            itemBuilder: (ctx, index) {
              final Service = Services[index].data() as Map<String, dynamic>;
              final ServiceId = Services[index].id;
              return Column(
                children: [
                  ListTile(
                    title: Text(Service['title']),
                    subtitle: Text(Service['price']),
                    trailing: IconButton(
                      icon: Icon(
                        Icons.delete,
                        color: Color.fromARGB(255, 184, 16, 16),),
                      onPressed: () async {
                        await FirebaseFirestore.instance
                            .collection('Services')
                            .doc(ServiceId)
                            .delete(); }, ),