Perhaps you should try some spelling variations:
vu khach » vu khanh, vu khac, vay khach
cam thuc » am thuc, nam thuc, cam thu
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
su sach » so sach
vu sach » vu bach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
hanh di » hanh vi, hanh de, hang di
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
ve cam » ve cham, ve cac, va cam
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: ((su sach) or (((vu sach) OR (vu khach)))) y nang xa hoi. hieu ve cam thuc dan hanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (((vu sach) OR (vu khach)))) y nang xa hoi. hieu ve cam thuc dan hanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (((vu sach) OR (vu khach)))) y nang xa hoi. hieu ve cam thuc dan hanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (((vu sach) OR (vu khach)))) y nang xa hoi. hieu ve cam thuc dan hanh di cua tre*.