Perhaps you should try some spelling variations:
nhanh thai » nhanh thi, nhanh thanh, nhanh thang
hieu van » hieu va, thien van, lieu va
van chat » cao chat
thai cua » than cua, tai cuc, tri cua
duc toan » duc ton, duc hoan, duc thang
sach ky » sac ky, sach ty, sach kem
cua tre » cua te, cuu tre, cua triet
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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 ky) or (sach y)) nang o hoi. hieu van chat ((duc toan) OR (duc tan)) nhanh thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach y)) nang o hoi. hieu van chat ((duc toan) OR (duc tan)) nhanh thai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) or (sach y)) nang o hoi. hieu van chat ((duc toan) OR (duc tan)) nhanh thai cua tre*".