Perhaps you should try some spelling variations:
quang dung » quang trung, ung dung, cuong dung
hanh tinh » hanh trinh, nhanh tinh, thanh tinh
trong dan » trong dang, trong san, trong tan
hieu cac » hieu luc, hieu va, hieu van
dan toan » van toan, dan than, manh toan
toan cau » toan cao, toan ban, toan tap
hieu ca » hieu cua, hieu va, hieu xa

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu ca) OR (hieu cac)) - hanh tinh quang dung trong dan toan cau~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu ca) OR (hieu cac)) - hanh tinh quang dung trong dan toan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu ca) OR (hieu cac)) - hanh tinh quang dung trong dan toan cau*.