Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
tan hanh » tan thanh, tang hanh, toan hanh
tu cach » tu cac
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
ve cac » va cac, vien cac
vi cua » vai cua
di cua » dai cua, doi cua, de cua
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: ((tu cach) or (thu sach)) ky nang x hoi. hieu ve cac duc tan hanh ((vi cua) OR (di cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thu sach)) ky nang x hoi. hieu ve cac duc tan hanh ((vi cua) OR (di cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (thu sach)) ky nang x hoi. hieu ve cac duc tan hanh ((vi cua) OR (di cua)) tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thu sach)) ky nang x hoi. hieu ve cac duc tan hanh ((vi cua) OR (di cua)) tre*.