power query sql filter with variable , value from excel cell

thank you very much for your kind answer 

i tried below as in your reply , received below error

"DataSource.Error: Microsoft SQL: Unclosed quotation mark after the character string ' '."

i tried below code first received error above   :

and [PLANT]='" & ThisWorkbook.Worksheets("PROJE_BILGILER").Cells(6,"BO").value & "'"

then i deleted quotation mark at the end of the line like below, i did not reveive error , but the RESULT  was empty. i tred also writing cell as number only lıke below but again no result. if i write not variable but consttant string like [PLANT]= "UTK" İT WORKS . but when i reference excel cell , like below , no error but no result 

and [PLANT]= '" & ThisWorkbook.Worksheets("PROJE_BILGILER").Cells(6,"BO").value & "'

and [PLANT]= '" & ThisWorkbook.Worksheets("PROJE_BILGILER").Cells(31,1).value & "'

then i tried below code

WHERE PLANT = '" & ThisWorkbook.WorkSheets("PROJE_BILGILER").Range("A31").Value & "'"

received below error

DataSource.Error: Microsoft SQL: An object or column name is missing or empty. For SELECT INTO statements, verify each column has a name. For other statements, look for empty alias names. Aliases defined as "" or [] are not allowed. Change the alias to a valid name.
Unclosed quotation mark after the character string ''.

sorry to bother you but this subject is very important for me ,  and after 1 month search could not find a solution .

looking for your kind reply sir

best regards