Perhaps you should try some spelling variations:
hanh tri » thanh tri, hanh tai, hanh trinh
te sach » toc sach
tri cuu » tri cua, tra cuu, trinh cuu
duc van » duc va, duc tan, duc manh
duc ban » duc tan, dua ban, duc man
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
nang co » nang doc, nang noi, nang hoc
ve cac » va cac, vien cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y ((nang cao) or (nang co)) hai. hieu ve cac ((duc ban) or (duc van)) hanh tri cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((nang cao) OR (nang co)) hai. hieu ve cac ((duc ban) OR (duc van)) hanh tri cuu tre.
• Adding a wildcard symbol may retrieve word variants: te sach y ((nang cao) or (nang co)) hai. hieu ve cac ((duc ban) or (duc van)) hanh tri cuu tre*.