Perhaps you should try some spelling variations:
trinh tu » trinh do
cam thuc » am thuc, nam thuc, cam thu
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
hanh lai » hanh lam, hanh tai, thanh lap
tinh ly » trinh ly, sinh ly, dinh ly
may hoi » may thoi, tay hoi, mai hoi
hieu ve » hieu va, hieu van
lai cua » dai cua, hai cua, lai chau
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: so ((tinh ly) or (((trinh tu) OR (trinh ky)))) mang may hoi. hieu ve cam thuc dan hanh lai cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((tinh ly) OR (((trinh tu) OR (trinh ky)))) mang may hoi. hieu ve cam thuc dan hanh lai cua vat*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((tinh ly) or (((trinh tu) OR (trinh ky)))) mang may hoi. hieu ve cam thuc dan hanh lai cua vat*".