Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
nang mai » nang ma, nang tai, lang mai
toc sach » hoc sach, thuoc sach, nuoc sach
va thanh » gia thanh, ban thanh, va tinh
doc sach » hoc sach, nuoc sach, dac sac
cac duc » cac du, cao duc, cac dac
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ly nang » ky nang, ly hang, ly vang
cua tre » cua te, cuu tre, cua triet
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) or (((toc sach) OR (doc sach)))) ly nang mai hoi. hieu ve cac duc va thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (((toc sach) OR (doc sach)))) ly nang mai hoi. hieu ve cac duc va thanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (((toc sach) OR (doc sach)))) ly nang mai hoi. hieu ve cac duc va thanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (((toc sach) OR (doc sach)))) ly nang mai hoi. hieu ve cac duc va thanh dai cua tre*.