Perhaps you should try some spelling variations:
hanh thai » nhanh thai, hinh thai, hanh tai
hieu van » hieu va, thien van, lieu va
thai cua » than cua, tai cuc, tri cua
duc manh » suc manh, duc anh, duc minh
duc van » duc va, duc tan, duc phan
van hac » van hoc, van ha, van hai
sach ky » sac ky, sach ty, sach kem
nang o » nang co, nang ho, nang ro
cua tu » cua tuc, cua su, cua cu
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 (sach y)) nang o hoc. hieu van hac ((duc van) OR (duc manh)) hanh thai cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach y)) nang o hoc. hieu van hac ((duc van) OR (duc manh)) hanh thai cua tu*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) or (sach y)) nang o hoc. hieu van hac ((duc van) OR (duc manh)) hanh thai cua tu*".