Hello Chanh Bao Lam
asdocx exports results not only to Word/Excel/LaTeX, but also keeps the formulated matrix on file, which we can modify as we may like. The asdocx matrix is shown on Stata screen with row and column numbering. These row and column numbering can be used to access the matrix parts. Therefore, if you wish to replace / delete columns/rows, you can use various sub-commands of flexmat (part of the asdocx package, type help flexmat to know more about it).
In your specific query, you want to drop few rows. Rows can be dropped using the droprow sub-command, with option row(), in which we specify the row numbers. In the following example, I shall drop row 9 and 10, once the asdocx output is ready.