The Search template appears in the template list when a numeric vector field, that is a field with an ordered set of multiple numbers, of x2 (two numbers), x3 (three numbers), or x4 (four numbers), numeric vector type has been picked in the Select pane. The template selects based on numeric vector values compared to the given value.
Search 
Select by making comparisons against the desired extraction from the numeric vector field specified in the Use parameter, using the given Condition, compared to the given value or values, which can be values from a field, a specified value, or the result of an expression that evaluates to a numeric value or to a datetime value depending on the data type of the extraction specified in the Use parameter.
Use options:
Condition options:
If we would like to select records that are NOT variations of the above, for example not between, select on the basis of one of the above and press CtrlI or Edit  Select Inverse to invert the selection. Selecting using between and then pressing CtrlI is the equivalent of "not between" the given values.
The Round box allows automatic rounding of the source field number before comparing to the specified value:
Launch the template by choosing a numeric vector field in the Select pane and then doubleclicking the Search template. When the template launches we can specify options.

Search : value 0 
Use the first component of the vector.

Search : value 1 
Appears with x2, x3 and x4 types. Use the second component of the vector.

Search : value 2 
Appears with x3 and x4 types. Use the third component of the vector.

Search : value 3 
Appears with x4 types. Use the fourth component of the vector. 
Search : vector 
Use the vector value in the source field.

Numeric vector types  Numeric vectors are fields that have ordered sets of multiple numbers, of x2 type float32x2, float64x2, int8x2, int16x2, int32x2, int64x2, uint8x2, uint16x2, uint32x2, uint6x2, of x3 type float32x3, float64x3, int8x3, int16x3, int32x3, int64x3, uint8x3, uint16x3, uint32x3, uint6x3, or of x4 type float32x4, float64x4, int8x4, int16x4, int32x4, int64x4, uint8x4, uint16x4, uint32x4, uint6x4.
Select  Numeric Vectors: Expression
Select  Numeric Vectors: Null