Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
toc sac » toc san, hoc sach, doc sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cua lao » cu lao, ca lao, cua dao
va hanh » van hanh, va thanh, va danh
ve cua » le cua, de cua, te cua
lao va » tao va, cao va, bao va
vi cua » vai cua
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((toc sac) or (toc sach)) ky nang xa hoi. hieu ve cua lao va hanh ((vi cua) OR (di cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((toc sac) OR (toc sach)) ky nang xa hoi. hieu ve cua lao va hanh ((vi cua) OR (di cua)) triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((toc sac) or (toc sach)) ky nang xa hoi. hieu ve cua lao va hanh ((vi cua) OR (di cua)) triet".
• Adding a wildcard symbol may retrieve word variants: ((toc sac) or (toc sach)) ky nang xa hoi. hieu ve cua lao va hanh ((vi cua) OR (di cua)) triet*.