Perhaps you should try some spelling variations:
hoc nganh » hoc nhanh
dang thai » dang thi, dang hai, dang khai
thai cua » than cua, tai cuc, tri cua
cac dac » cac dan, cac dai, cac bac
va dang » van dang, va nang, va lang
cac duc » cac du, cao duc, cac nuoc
hieu ve » hieu va, hieu van
van hoi » van hoc, van hoe, van loi
cua tre » cua te, cuu tre, cua triet
y lang » o lang, _ lang, tay lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc nganh y lang ((van hoi) or (van hoa)). hieu ve ((cac duc) or (cac dac)) va dang thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc nganh y lang ((van hoi) OR (van hoa)). hieu ve ((cac duc) OR (cac dac)) va dang thai cua tre.
• Adding a wildcard symbol may retrieve word variants: hoc nganh y lang ((van hoi) or (van hoa)). hieu ve ((cac duc) or (cac dac)) va dang thai cua tre*.