Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thu sach » tu sach, thuat sach, thu hoach
dau tren » dau tien, dat tren, dau tieng
va hanh » van hanh, va thanh, va danh
hanh ve » hanh vi, hanh va, hanh kem
cam lo » nam lo, cam ly, cam o
ve dau » va dau, ve du, ke dau
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) or (thuoc sach)) ky nang x hoi. lieu va ((cam loc) OR (cam lo)) va hanh ve dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuoc sach)) ky nang x hoi. lieu va ((cam loc) OR (cam lo)) va hanh ve dau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) or (thuoc sach)) ky nang x hoi. lieu va ((cam loc) OR (cam lo)) va hanh ve dau tren".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) or (thuoc sach)) ky nang x hoi. lieu va ((cam loc) OR (cam lo)) va hanh ve dau tren*.