Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
dua tren » dung tren
hanh dai » hanh tai, hanh dao, vanh dai
van hanh » van thanh, ban hanh, van anh
duc van » duc va, duc tan, duc manh
va cao » va cac, va co, va dao
y nang » ky nang, ly nang, v nang
ve cao » ve bao, ve cac, ve co
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: thu sach y nang x hoi. hieu ((ve cao) OR (va cao)) duc van hanh dai ((dua tren) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang x hoi. hieu ((ve cao) OR (va cao)) duc van hanh dai ((dua tren) OR (cua te))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang x hoi. hieu ((ve cao) OR (va cao)) duc van hanh dai ((dua tren) or (cua te))*".