Retrieve Similar Value From Another Sheet?

I have an excel grid which have 2 sheets, sheet2 have all the data, I am doing a macro which based on a value that I put in sheet1 is supposed to find Items which have similar value +/-3 from sheet1. I made a code which I posted below, I don't have any error message but it doesn't work as it should. I explain you with an example: If in the data grid I have the following values

11.8
67.0
25.5
18.1
13.0

if the value I look for is 12 +/-3, it doesn't find anything.
if the value I look for is 11 +/-3, it finds 11.8 but not 13,
if the value I look for is 20 +/-3, it finds 18.1,
if the value I look for is 23 +/-3, it finds 25.5,

Here is my code:

Sheet1.Cells(1, 3).Select
Dim Amin As String, Amax As String ', Bmin As String, Bmax As String
Amin = Sheet1.Cells(3, 2).Value - 3

[Code].....