Perhaps you should try some spelling variations:
manh thanh » danh thanh, minh thanh, manh thang
thanh gia » thanh gian, thanh giang, thanh nghia
hieu vien » hieu hien, hieu viec, thieu nien
cua viet » ca viet, hoa viet, cua vat
sach ky » sac ky, sach ty, sach kem
cac duc » cao duc, cac dac, cac nuoc
gia cua » gian cua, giau cua, gia cuc
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: tu ((sach ky) OR (sach y)) nang o hoi. hieu vien ((cac duc) or (cac du)) manh thanh gia cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach y)) nang o hoi. hieu vien ((cac duc) OR (cac du)) manh thanh gia cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sach y)) nang o hoi. hieu vien ((cac duc) or (cac du)) manh thanh gia cua viet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sach y)) nang o hoi. hieu vien ((cac duc) or (cac du)) manh thanh gia cua viet*.