Perhaps you should try some spelling variations:
dao thanh » ban thanh, tro thanh, de thanh
cam thuc » am thuc, nam thuc, cam thu
dao hanh » dang hanh, ban hanh, dao van
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
va cam » va cham, va cac, va cao
di cua » doi cua, de cua, do 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: vu sach ky nang x hoi. hieu va cam thuc ((dao hanh) or (dao thanh)) ((di cua) OR (dai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang x hoi. hieu va cam thuc ((dao hanh) OR (dao thanh)) ((di cua) OR (dai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ky nang x hoi. hieu va cam thuc ((dao hanh) or (dao thanh)) ((di cua) OR (dai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang x hoi. hieu va cam thuc ((dao hanh) or (dao thanh)) ((di cua) OR (dai cua)) tre*.