Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
va hanh » va thanh, va danh, ban hanh
nang xa » nang x, lang xa, nang ma
sach ky » sac ky, sach y, sach ty
di cua » dai cua, doi cua, de cua
ve tai » te tai, de tai, le tai
ve cai » va cai, ve cac, ve cau
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: toc sach ky nang xa hoi. hieu ((ve cai) OR (ve tai)) lao ((va hanh) or (van hanh)) di cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang xa hoi. hieu ((ve cai) OR (ve tai)) lao ((va hanh) OR (van hanh)) di cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ky nang xa hoi. hieu ((ve cai) OR (ve tai)) lao ((va hanh) or (van hanh)) di cua te".
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. hieu ((ve cai) OR (ve tai)) lao ((va hanh) or (van hanh)) di cua te*.