Scroll to a given field and press Ctrl+F or Ctrl+Enter or click the Search button or use the Tools > Set Search Filter command.
Filters specified for more than one field at the same are assumed to be merged by the AND logical operator and narrow down the search results.

• The displayed Search dialog box enables you to specify the filter and its type.
  
  • Regular expressions
  • "Starts with", text patterns with the * and ? masks
  • Equal, Not Equal, Greater than, Smaller than
  • Between
  • AND, OR
  • IsEmpty (also after removing whitespaces)
  • Similar ("fuzzy" searches)
  • Flagged records (with user-defined flags)
  • Formula (including over 300 functions and references to fields in one record)
  To search for the currently selected field value, click the "=" button or press Ctrl + =.
• The default filter type for text fields is Regular Expression and for numeric fields: Equal.
• After a given filter type is used for some field, it becomes its default type.
• The default initial filter type can be changed in the Settings > Options dialog box.
• Allow empty matches and Match case are two options used by the Regular Expression filter type only.
  Empty matches occur for Regular Expression like \A\z or a? .
• Selecting the default Seearch All Now option causes instant re-searching
  all fields after you click OK. Turning it off should be helpful and prevent unnecessary re-searching
  especially when entering relatively many filters (with the limit same as the field/column limit: 16K)
  for large data sets. After you enter them, you just use the command Search All Now (Ctrl+F9)

There are three filter types available for numeric and text fields:

1. Regular Expressions (RegEx) - the filter string is a data pattern based on standard regular expression syntax. You can click the "?" button to display a list of commonly used expressions. Some examples of regular expressions:

   abc - matches substrings "abc",

   .bc - matches three character substrings consisting of any character followed by "bc",

   \Aabc - matches field contents starting with "abc",

   abc\z - matches field contents ending with "abc",

   \Aabc.*123\z - matches field contents starting with "abc" and ending with "123" with any number of other characters in between,

   abc\d\z - matches substrings ending with "abc" and one digit,

   ^a\d+ - matches field contents containing a line starting with "a" and at least one digit,

   ^a\d* - matches field contents containing a line starting with "a" and zero or more digits,

   [ab]+c - matches substrings "abc", "aabc", "abbabc" etc. and not "c",

   [ab]*c - matches substrings "abc", "aabc", "abbabc" etc. and "c",

   [^ab]+c - matches substrings ending with "c" and not containing "a" or "b",

   \w\d{2,3} - matches substrings consisting of one letter followed by 2 or 3 digits,

   \Aab\d{2,3}c - matches field contents beginning with "ab", two or three digits and "c",

   abc|xyz - matches substrings "abc" or "xyz",

   \A\z - matches empty fields,

   For more information, see PCRE regular expression syntax summary

2. Plain text (Starts with, Equal, Not equal, ...) - the filter string represents a plain text string that is compared against the whole field contents. This filter category includes a few variants: "Pattern", "Equal", "Not equal", "Greater than", "Less than", "Between", "And" and "Or".
   For the "Starts with", "And" and "Or" variants the filter string can be a prefix of the compared strings and can contain wildcard "?" and "*" characters. Any non-wildcard "?" and "*" characters must be prefixed with a tilde (~).
   The remaining variants perform exact text string comparisons. For "Between", "And" and "Or" the entered filter must be a list of respectively two or more elements separated by spaces.
   Examples:

   abc - matches field contents beginning with "abc" ("Starts with"),

   ?bc - matches field contents beginning with any character followed by "bc" ("Starts with"),

   *abc - matches field contents ending with any character followed by "abc" ("Starts with"),

   * - matches all non-empty field contents ("Starts with"),

   50.1 100.2 - matches values equal to or between 50.1 and 100.2 ("Between", US regional numeric settings),

   12/1/2012 12/31/2012 - matches dates equal to or between the specified ones ("Between", US regional date settings),

   ab cd *ef - matches field contents equal to "ab", "cd" or ending with "ef" ("Or")

3. Formulas - the filter string represents a formula expression that can make use of the all the built-in functions, operators and references to other record fields. The formulas are similar to those used in spreadsheets with a few exceptions:

   cell references are replaced by field names,

   the range ":" operator is not available,

   direct references to other tables via the "!" and "_" operators are not available.

   When searching, such a formula is evaluated for each record and a given record is considered to meet the searching criteria if each the formula returns a non-zero value.

   To learn more about building formulas, see: Entering formulas

4. Flagged records - searching for records flagged/marked by a given flag, which is a unique combination of field font and background colors.

Long Text, Images/Files and Code fields always use Regular Expressions to filter records. When filtering Images/Files fields, the file names are searched.

Clicking the "Paste" displays a list of recently entered search strings.

To remove all specified search filters, click the (None) search key on the toolbar or use the Tools > Reset Searching command.

Scroll to a field or select a range of fields which should be searched and use the Tools > Find Duplicates command.
To find duplicated (whole) records, select an entire row clicking the row heading or pressing Shift+Space.

To find the complement of the current record set (that is, all the records that are not included in the current record set), use the Tools > Find Complement command.

Use the Edit > Find (F3) command and in the displayed Search Toolbar enter the desirable substring. The Find Previous/Next commands simply scroll to the subsequent found table or form cell values. The Find All command performs full-text filtering of Text and Numeric fields (Long Text fields are not included).
The search toolbar also enables you to replace found substrings. If you want to perform such a find-and-replace action for one field only, select the column clicking its header.