You can add an action called <On Key Press> to your Text Field, which will execute whenever a key is pressed (see http://www.tersus.com/#Id=3182 for details on this and other event handlers).
This action can perform any logic you wish, including retrieving the current content of the field's <Value> element, performing a database query (using Find/Advanced Find) based on the retrieved value, and updating the display according to the results.
Regarding the "sql LIKE condition", basically Tersus accesses the database using SQL, translating each of the database actions into the appropriate SQL statement, so for example, Advanced Find is converted into a SELECT statement, and its <Filter> to the SELECT's WHERE clause - for more details see http://www.tersus.com/#Id=3439.As you may realise from the abive, some knowledge of SQL would be helpful if you wish to implement more than basic functionality in your apps. I suggest you google "sql LIKE condition" for more information.
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