Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
thai cua » than cua, tai cuc, tri cua
tan hanh » tan thanh, tang hanh, toan hanh
chat duc » chat xuc, chat doc, chet duoc
van chat » cao chat
hieu van » hieu va, thien van, lieu va
cua tre » cua te, cuu tre, cua triet
sach ky » sach ty, sach kem, sach hay
nang o » nang co, nang ho, nang ro
sac ky » cac ky, sai ky
o hoc » co hoc, mo hoc, so hoc

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