Perhaps you should try some spelling variations:
yen lang » den lang, ten lang, yen giang
tu sach » thu sach, su sach, te sach
van hoc » van hoa
qua cau » quan cau, qua cac, qua ca
cau luc » cau truc, cau phuc
va hanh » van hanh, va thanh, va danh
hanh di » hanh vi, hanh de, hang di
o lang » hoa lang, hoi lang
luc va » duc va, tuc va, loc va
di cua » dai cua, doi cua, de cua
cua te » cua tu

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 ((yen lang) or (o lang)) van hoc. hieu qua cau luc va hanh di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((yen lang) OR (o lang)) van hoc. hieu qua cau luc va hanh di cua te.
• Adding a wildcard symbol may retrieve word variants: tu sach ((yen lang) or (o lang)) van hoc. hieu qua cau luc va hanh di cua te*.