Perhaps you should try some spelling variations:
phan dau » phan tu, hang dau
sach thu » sach thue, sach thieu, sach tham
van hanh » van thanh, ban hanh, van anh
van dau » van dao
hanh de » hanh ve, hanh kem
luc van » luoc van, luu van, duc van
de cua » le cua, te cua, dieu cua
sac ky » cac ky, sai ky
cua te » cua tu
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sac ky) or (sach thu)) nang x hoi. hieu ((van dau) OR (phan dau)) luc van hanh de cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sac ky) OR (sach thu)) nang x hoi. hieu ((van dau) OR (phan dau)) luc van hanh de cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sac ky) or (sach thu)) nang x hoi. hieu ((van dau) OR (phan dau)) luc van hanh de cua te*".