Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
toc sach » hoc sach, doc sach, thuoc sach
thu nang » thi nang, thu hang, thu bang
hieu van » hieu va, thien van, lieu va
hanh vai » hanh vi, hanh va, hanh tai
cua cau » cua cac, cua chu, cua can
van cac » van hac, van cau, van bac
duc van » duc va, duc tan, duc manh
cac duc » cac du, cao duc, cac dac
cao hoc » co hoc, cho hoc, chat hoc
cua cay » cua cac

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) thu nang cao hoc. hieu van cac duc van hanh vai ((cua cau) OR (cua cay))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) thu nang cao hoc. hieu van cac duc van hanh vai ((cua cau) or (cua cay))~".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) thu nang cao hoc. hieu van cac duc van hanh vai ((cua cau) or (cua cay))*.