Perhaps you should try some spelling variations:
thieu nien » thien nhien
manh hanh » xanh hanh, danh thanh, minh thanh
nien cac » vien cac, dien cac, bien cac
duc manh » suc manh, duc anh, duc minh
thai cua » than cua, tri cua, dai cua
sach ty » sach tu, sach thu, xach tay
cac duc » cac du, cao duc, cac dac
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 ty) or (sach y)) nang o hoi. thieu nien cac duc manh hanh ((thai cua) OR (tai cuc)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sach y)) nang o hoi. thieu nien cac duc manh hanh ((thai cua) OR (tai cuc)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ty) or (sach y)) nang o hoi. thieu nien cac duc manh hanh ((thai cua) OR (tai cuc)) tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach ty) or (sach y)) nang o hoi. thieu nien cac duc manh hanh ((thai cua) OR (tai cuc)) tre*.