[Страдалецъ]

Скорее всего ошибка в передаваемых данных.
Вот рабочий примерчик:

Код:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, DB, ADODB, StdCtrls, Grids, DBGrids;

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Edit2: TEdit;
    DBGrid1: TDBGrid;
    Label1: TLabel;
    Label2: TLabel;
    dsQuery: TDataSource;
    Query: TADOQuery;
    AppDB: TADOConnection;
    Queryid: TAutoIncField;
    QueryПреподаватель: TWideStringField;
    QueryДисциплина1: TWideStringField;
    QueryДисциплина2: TWideStringField;
    QueryДисциплина3: TWideStringField;
    Edit3: TEdit;
    Label3: TLabel;
    procedure FormCreate(Sender: TObject);
    procedure EditChange(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure Tform1.EditChange(Sender: TObject);
begin
 Query.Close;
 Query.SQL.Text := 'select * from Исполнители where [Преподаватель] like :Value1 and [Дисциплина №1] like :Value2 and [Дисциплина №2] like :Value3';
 Query.Parameters.ParamValues['Value1'] := Edit3.Text + '%';
 Query.Parameters.ParamValues['Value2'] := Edit1.Text + '%';
 Query.Parameters.ParamValues['Value3'] := Edit2.Text + '%';
 Query.Open;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
 AppDB.Open;
 EditChange(Sender);
end;
end.

object Form1: TForm1
  Left = 0
  Top = 0
  Caption = 'Form1'
  ClientHeight = 302
  ClientWidth = 635
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  OnCreate = FormCreate
  PixelsPerInch = 96
  TextHeight = 13
  object Label1: TLabel
    Left = 201
    Top = 33
    Width = 67
    Height = 13
    Caption = #1044#1080#1089#1094#1080#1087#1083#1080#1085#1072'1'
  end
  object Label2: TLabel
    Left = 325
    Top = 33
    Width = 67
    Height = 13
    Caption = #1044#1080#1089#1094#1080#1087#1083#1080#1085#1072'2'
  end
  object Label3: TLabel
    Left = 88
    Top = 33
    Width = 80
    Height = 13
    Caption = #1055#1088#1077#1087#1086#1076#1072#1074#1072#1090#1077#1083#1100
  end
  object Edit1: TEdit
    Left = 201
    Top = 48
    Width = 118
    Height = 21
    TabOrder = 1
    OnChange = EditChange
  end
  object Edit2: TEdit
    Left = 325
    Top = 48
    Width = 121
    Height = 21
    TabOrder = 2
    OnChange = EditChange
  end
  object DBGrid1: TDBGrid
    Left = 8
    Top = 75
    Width = 619
    Height = 120
    DataSource = dsQuery
    TabOrder = 3
    TitleFont.Charset = DEFAULT_CHARSET
    TitleFont.Color = clWindowText
    TitleFont.Height = -11
    TitleFont.Name = 'Tahoma'
    TitleFont.Style = []
  end
  object Edit3: TEdit
    Left = 88
    Top = 48
    Width = 112
    Height = 21
    TabOrder = 0
    OnChange = EditChange
  end
  object dsQuery: TDataSource
    DataSet = Query
    Left = 528
    Top = 192
  end
  object Query: TADOQuery
    Active = True
    Connection = AppDB
    CursorType = ctStatic
    Parameters = <>
    SQL.Strings = (
      'select * from '#1048#1089#1087#1086#1083#1085#1080#1090#1077#1083#1080)
    Left = 528
    Top = 144
    object Queryid: TAutoIncField
      DisplayWidth = 12
      FieldName = 'id'
      ReadOnly = True
    end
    object QueryПреподаватель: TWideStringField
      DisplayWidth = 23
      FieldName = #1055#1088#1077#1087#1086#1076#1072#1074#1072#1090#1077#1083#1100
      Size = 255
    end
    object QueryДисциплина1: TWideStringField
      DisplayWidth = 23
      FieldName = #1044#1080#1089#1094#1080#1087#1083#1080#1085#1072' '#8470'1'
      Size = 255
    end
    object QueryДисциплина2: TWideStringField
      DisplayWidth = 24
      FieldName = #1044#1080#1089#1094#1080#1087#1083#1080#1085#1072' '#8470'2'
      Size = 255
    end
    object QueryДисциплина3: TWideStringField
      DisplayWidth = 29
      FieldName = #1044#1080#1089#1094#1080#1087#1083#1080#1085#1072' '#8470'3'
      Size = 255
    end
  end
  object AppDB: TADOConnection
    Connected = True
    ConnectionString = 
      'Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\'#1061#1086#1079#1103#1080#1085'\Doc' +
      'uments\Demo.mdb;Persist Security Info=False'
    LoginPrompt = False
    Mode = cmShareDenyNone
    Provider = 'Microsoft.Jet.OLEDB.4.0'
    Left = 528
    Top = 96
  end
end