Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
thu sac » thu san, thu xac, thu dac
va hanh » van hanh, va thanh, va danh
hai chu » hai chau, hoi chu, hai chi
hai cuu » hai cua, hai cuc, thai cua
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
cac lo » cac lop, cac co, cac bo
lo va » lo van, lao va, ly va

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

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