Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thu sach » tu sach, thuoc sach, thu hoach
cau tren » cu tren, dau tren, ca tren
nang toc » nang doc, nang hoc, nang thuc
toc hoc » toan hoc, duoc hoc
vu cham » va cham, vu kham, tu cham
va hanh » van hanh, va thanh, va danh
hanh va » hang va, hanh vi
va chat » van chat, va phat, cao chat
va cau » van cau, va cac, va dau

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 (thuat sach)) ky nang toc hoc. hieu ((va chat) or (vu cham)) duc va hanh va cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuat sach)) ky nang toc hoc. hieu ((va chat) OR (vu cham)) duc va hanh va cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (thuat sach)) ky nang toc hoc. hieu ((va chat) or (vu cham)) duc va hanh va cau tren".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) OR (thuat sach)) ky nang toc hoc. hieu ((va chat) or (vu cham)) duc va hanh va cau tren*.