Perhaps you should try some spelling variations:
truong doi » truong dai, trong doi, truong hoi
so sach » so sanh, bo sach, hoc sach
doi cua » dai cua, hoi cua
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
ty nang » ky nang, ty xang, ty hang
co sach » bo sach, cuon sach, hoc sach
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai
tu xa » tu xay, tu va, tu ma
te xa » te va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (co sach)) ty nang o hoi. hieu va cac ((tu xa) OR (te xa)) truong doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (co sach)) ty nang o hoi. hieu va cac ((tu xa) OR (te xa)) truong doi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (co sach)) ty nang o hoi. hieu va cac ((tu xa) OR (te xa)) truong doi cua tre".
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (co sach)) ty nang o hoi. hieu va cac ((tu xa) OR (te xa)) truong doi cua tre*.