Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
sach doi » sach hoi, sach moi, sach dao
va thanh » gia thanh, ban thanh, va tinh
cam duc » cam xuc, cao duc, nam duoc
hieu va » lieu va, hieu qua
tu sach » thu sach, su sach, te sach
lang ha » long ha
nang xa » nang x, lang xa, nang ma
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: tu sach doi ((nang xa) or (lang ha)) hoi. hieu va ((cam duc) OR (pham duc)) va thanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach doi ((nang xa) OR (lang ha)) hoi. hieu va ((cam duc) OR (pham duc)) va thanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach doi ((nang xa) or (lang ha)) hoi. hieu va ((cam duc) OR (pham duc)) va thanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach doi ((nang xa) or (lang ha)) hoi. hieu va ((cam duc) OR (pham duc)) va thanh dai cua tre*.