Perhaps you should try some spelling variations:
"thi hanh nam sinh duoc." » "thi hanh nam sinh hoc.", "thi thanh nam sinh duoc.", "thi hanh lam sinh duoc.", "thi hanh ngay sinh duoc.", "thi hanh nam dinh duoc.", "thi hanh nam linh duoc.", "thi hanh tam sinh duoc."
"theo cach mang anh duc." » "theo sach mang anh duc.", "tho cach mang anh duc.", "tho cac mang anh duc.", "theo cach mang xanh duc.", "theo cach bang anh duc.", "theo cach hoang anh duc."
"te sach cao minh duc." » "te sach dao minh duc.", "te sach cap minh duc.", "te mach cao minh duc.", "te sach chi minh duc.", "te sach van minh duc.", "toc sach cao minh duc."

You may be able to get more results by adjusting your search query.

• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"te sach cao minh duc.\") OR (\"theo cach mang anh duc.\"))) OR (\"thi hanh nam sinh duoc.\"))~".
• Removing quotes may allow a broader search: (((( te sach cao minh duc. ) OR ( theo cach mang anh duc. ))) OR ( thi hanh nam sinh duoc. ))~.
• Adding a wildcard symbol may retrieve word variants: (((("te sach cao minh duc.") OR ("theo cach mang anh duc."))) OR ("thi hanh nam sinh duoc."))*.