Perhaps you should try some spelling variations:
day nhanh » day thanh, duy nhanh, dac nhan
cam thuc » am thuc, nam thuc, cam thu
day hanh » day thanh, dao hanh, day manh
vu sach » vu bach, su sach, vu khach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
hieu ve » hieu va, hieu van
ve cam » ve cham, ve cac, va cam
di cua » dai cua, doi cua, de cua
cua tu » cua tuc, cua su, cua cu

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 ty nang x ho. hieu ve cam thuc ((day hanh) or (day nhanh)) di cua tu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty nang x ho. hieu ve cam thuc ((day hanh) OR (day nhanh)) di cua tu.
• Adding a wildcard symbol may retrieve word variants: vu sach ty nang x ho. hieu ve cam thuc ((day hanh) or (day nhanh)) di cua tu*.