Perhaps you should try some spelling variations:
dang thanh » dong thanh, dang hanh, hoang thanh
thuat sach » thuat lanh, thuat san
dang than » sang than, dang tran, dan than
sach ky » sac ky, sach y, sach ty
dan bac » dan ba, van bac, dong bac
van bao » van ban, van dao
cua tre » cua te, cuu tre, cua triet

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky nang x ho. thi ((dan bac) or (van bao)) nuoc va ((dang than) OR (dang thanh)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky nang x ho. thi ((dan bac) OR (van bao)) nuoc va ((dang than) OR (dang thanh)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky nang x ho. thi ((dan bac) or (van bao)) nuoc va ((dang than) OR (dang thanh)) cua tre".
• Adding a wildcard symbol may retrieve word variants: thuat sach ky nang x ho. thi ((dan bac) or (van bao)) nuoc va ((dang than) OR (dang thanh)) cua tre*.